Weaving the World Wide Web
The HTML Language

# HTML Tags: The Reference

## Background

This is a compendium of all of the HTML tags I can get my hands on. It may not always be complete, but we'll try to keep it as up to date as possible.
Image handling tags and table handling tags also have their own separate pages, as they require more in-depth discussion than this listing offers.

If you find errors or parts which need updating, please take the time to send a message letting us know.

## Using This Reference

There are several things you should know about this listing, before you use any of the tags described within:

### Case Insensitivity

In the listing of tags, I have written the tags out in capital letters. I have done this for readability only: tags are NOT case sensitive! This means that <CENTER> will be interpreted the same as <center>, <CeNtEr>, and <cENTEr>.

### Under Construction

Currently, this document is being revised to include to follow the
HTML 3.2 specifications, with an addition of the Microsoft Internet Explorer 3.0 Extensions, and the Netscape Navigator 3.0 Extensions. Due to the volume of HTML specifications, this reference is very frequently under construction.

### Closing Tags

Be certain, when using tags that require closing tags, that you not only use the closing tags, but that you try to close paired tags in the same manner you opened them in. The seminar to which this reference belongs has a lengthier discussion about containers.

### Attributes

All of the attributes which the author of this document could locate are listed with their tags. Attributes which can take exactly one of any number of specific options as its value have those options listed, separated by the vertical bar character ("|"). Ergo, an attribute listed as:

SHAPE=circle|square|poly

can be set to either "circle", "square", or "poly" (but not to "circle, poly"). Some attributes as well do not require values; simply stating the attribute is all that is required (such as the ISMAP attribute of the IMG tag).

### Sources

This document was built by Mark Hazen, in March of 1997. The sources used for this document include the W3 specifications documents for both HTML 3.2 and HTML 2.0, as well as the Microsoft HTML Reference for Internet Explorer 3.0, and notes collected from the Netscape 3.0 Release Notes. As with any work drawn from multiple overlapping sources, many inconsistencies between source documents were noted (especially between the Microsoft Reference and anything else on the face of the planet). Where this occured, the HTML 3.2 and 2.0 specifications from the W3 Consortium were used as the judging rule. I felt this was the fairest judge, as both Microsoft and Netscape were voting members in the ratification process for the HTML 3.2 standard. Having taken these pains to verify tags, I hope you will agree that the resource before you is one of, if not the most, current and correct in existence.

### Symbols Used In This Listing

Several symbols are used throughout this page to denote characteristics of tags. These symbols are:
 This symbol signifies that the tag in question is a part of the HTML 3.2 standard, as ratified and recommended by the W3 Consortium. This symbol signifies that the tag in question was last referenced in the the HTML 2.0 standard, as ratified and recommended by the W3 Consortium. This symbol signifies that the tag in question is comprehended and rendered by the Netscape Navigator browser, as of version 3.01. A smaller version of this icon is also used to mark browser-specific extended tag attributes understood by the Netscape 3.01 browser. This symbol signifies that the tag in question is comprehended and rendered by the Microsoft Internet Explorer browser, as of version 3.01. A smaller version of this icon is also used to mark browser-specific extended tag attributes understood by the Microsoft 3.01 browser. This signifies that the tag in question is an extended tag not included in an offiially ratified W3 standard. Some of these tags are extensions which are under development by the W3 Consortium, but most of these are actually proprietary extensions added in by individual browser producers. This icon signifies that the given tag represents a physical rendering style. Physical references indicate a specific change to the text style such as bolding or underlining, which will vary in appearance from platform to platform. This symbol signifies that the given tag causes a logical change in rendering style; this change may or may not be visibly apparent, but is designed to denote specific types of informational data, such as program output, typed keystrokes, and the like. Tags marked with this icon are deprecated, and are no longer a part of the HTML standard and have officially been removed from the listings; they are still supported by modern browsers, but only at the discretion of browser producers. These tags should be avoided.

## The HTML Tags

Clicking on a tag in the listing below will take you to the description for that tag.

<!-- -->  !DOCTYPE  A  ADDRESS  APPLET  AREA  B  BASE  BASEFONT  BGSOUND  BIG  BLINK  BLOCKQUOTE  BODY  BR  CAPTION  CENTER  CITE  CODE  COL  COLGROUP  COMMENT  COMMENT  DD  DFN  DIR  DIV  DL  DT  EM  EMBED  FONT  FORM  FRAME  FRAMESET  HEAD  HR  HTML  Hn  I  IMG  INPUT  ISINDEX  KBD  LI  LINK  KBD  LI  LINK  LISTING  MAP  MARQUEE  MENU  META  MULTICOL  NOBR  NOEMBED  NOFRAMES  OBJECT  OL  OPTION  P  PARAM  PLAINTEXT  PRE  S  SAMP  SCRIPT  SELECT  SMALL  SPACER  SPAN  STRIKE  STRONG  STYLE  SUB  SUP  TABLE  TBODY  TD  TEXTAREA  TFOOT  TH  THEAD  TITLE  TR  TT  U  UL  VAR  WBR  XMP

## <!-- -->

ATTRIBUTES:
none

This tag allows users to insert comments into their HTML documents, which are not displayed onscreen when the document is viewed in a browser. If one were to take a look at the source of the document, however, the comment is visible. Any comments are indeed sent by the web server, but just ignored by the web browser.

According to RFC 1866, the guiding document for HTML 2.0:

To include comments in an HTML document, use a comment declaration. A comment declaration consists of '<!' followed by zero or more comments followed by '>'. Each comment starts with '--' and includes all text up to and including the next occurrence of '--'. In a comment declaration, white space is allowed after each comment, but not before the first comment. The entire comment declaration is ignored.
Therefore, the following is correct:
 <!-- This is a comment. This comment takes up more than one line. --> 
... as is this, as well:
 <!-- This is four comments. -- -- These comments are spread -- -- over -- --three lines.--> 
... but this is not a legal comment, even though most browsers will simply ignore it:
 <! This is not a comment. It is an error.> 
Comments are often used in conjunction with web-server specific features known as server-side includes, which allow HTML authors to include specialized commands within HTML documents. These commands can do things such as placing the time and date of the last modification for a file within a web page automatically, as well as file sizes, or possibly the output of web-server programs which use the common gateway interface (referred to as CGI programs).

## <!DOCTYPE>

ATTRIBUTES:
none

This tag, called a document type declaration, is used to denote which HTML specification a document complies with. As a definitive part of the HTML 3.2 standard, <!DOCTYPE> should also be the first element in any HTML document you write from this point out. !DOCTYPE is required to be the first line of a document, in order to be fully HTML 3.2 compliant.

To specify that your document follows the HTML 3.2 standard, you would insert this as the very first line of the HTML file:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
 There are other document type definitions which it is possible to write HTML to comply with. One of the most notable is:  This is the document type definition for a document following the HTML 2.0 standard, as specified in RFC 1866 (the document which defined the previous standard of HTML. A document which is labelled as "Strict" must not use different structural formatting, nor make any omissions of "recommended" items within the HTML 2.0 standard, or use any browser-specific tags. Needless to say, few documents on the web today fit this specification, but many technical documents found on the web will conform to this specification. The document type definition (also called a dtd for short) is actually a structure taken from SGML, the "parent" language, as it were, of HTML. All true SGML documents also all carry document type definition reference tags, pointing to whichever dtd they conform to.

## <A>....</A>

ATTRIBUTES:
HREF=url
REL=relationship
REV=relationship
TARGET=window name

The A tag (which stands for ANCHOR) allows one to make hyperlinks to other objects, whether those objects are other web pages, media types, or even people (thtough the use of the mailto: URL scheme).

The most common use for the <A> tag is to link to other HTML documents. In order to do this, the user only needs to include the href attribute and give it the value of whatever URL the link is intended to connect to, and provide an element between the opening and closing anchor tags, like so:

<a href="URL">(Element here) </a>

The element, in this case, is text or an image (simply put, any visibly renderable element) which would instill in the viewer knowledge of where such a link would lead them.

When you look at a page rendered in a browser, elements surrounded by anchor tags are automatically highlighted. More help is available on URLs if you require it.

The name attribute is used to allow users to mark portions of documents with a name unique to the scope of the document, which is used to associate a URL with the named portion of the document. in practice, this frequently looks like:

<a name="section_name">(Section here) </a>

To create an anchor tag within the same document linking back to this point, the user would surround the link element section with HTMl similar to the following:

<a href="URL#section_name">(Element here) </a>

To create a link in another document which would send browsers to the named section, the section name, following the # symbol, would be attached to the page's URL, as follows:

<a href="URL#anchor_name">(Element here) </a>

The rel attribute is used to allow HTML authors to name the relationship between the document in which a link is found, and the object to which the link leads. For example, having rel="index" included in an anchor tag would infer that the document being linked to is an index of the page in which the link was found.

The rev attribute implies just the opposite; having rev="index" included in an anchor tag would infer that the document being linked to is indexed by the page in which the link was found.

The title attribute allows the HTML author to provide an advisory title for the linked object within the link itself; thus, a hypertense HTML author might actually give you the title of the object in question, without you having to see the object at all.

In practice, maintaining correct relationships between pages is so utterly time consuming without the addition overhead of rel, rev, and title attributes inside of anchor tags, that you'll be hard pressed to find individuals using these three attributes to any degree whatsoever.

The target attribute is an attribute supported only by FRAME-capable browsers, used to specify the exact browser window or frame in which you want the link object to be loaded into. The value for target is either a name given by the HTML author, or one of the following four predefined window names:

NAME  RESULT
parentloads into the window which spawned the active window
toploads into the full body of the current window

ATTRIBUTES:
none

The ADDRESS tag is, like the Hn header tags, a block-level tag used to contain the address information of the individual or organization which the HTML author is identifying with a given paragraph or page.

The ADDRESS tag has no attributes, and formats line breaks before its opening tag and after its closing tag. Text placed inside of ADDRESS tags looks like this:

Mark Hazen
200 Dawson Hall
The University of Georgia

## <APPLET>....</APPLET>

ATTRIBUTES:
ALIGN=left|center|right|top|middle|bottom
ARCHIVE=zipped filename
CODE=applet filename (required)
CODEBASE=applet's base url
HEIGHT=height in pixels (required)
HSPACE=horizontal gutter, in pixels
NAME=applet name
VSPACE=vertical gutter, in pixels
WIDTH=width in pixels (required)

The <APPLET>....</APPLET> tags delineate the information needed to embed a Java applet into an HTML page. The APPLET tags constitute a container in which the opening tag contains information about which applet is to be loaded, its positioning, and its base url; between the opening tag and the closing tag, however, additional information may be specified for use by the applet, in the form of PARAM tags.

Here's an example of what the HTML source to embed an applet might look like. Please note, of course, that the items named by the PARAM tags would vary, depending on what input your Java applet needed:

<applet code="trajectory.class" width=400 height=300
name="Trajectory"  align=center alt="This requires Java">
<param name="numObjects" value="3">
<param name="gravLevel" value="50">
<param name="title" value="Three Object Trajectory">
</applet>



## <AREA>

ATTRIBUTES:
SHAPE=rect|circle|poly
COORDS=x1 , y1 ... xn , yn
URL=url
NOHREF
ALT=text

The <AREA> tag is used to define a shape within a client-side imagemap's <MAP>....</MAP> element. These individual AREAs define the link between a specific region of an image being used as a client-side imagemap, and the URL to which that region is linked.

The possible shapes of an AREA are defined by the collective points as listed below:

SHAPE  DEFINED BY:
recttopleft(x), topleft(y), bottomright(x), bottomright(y)
polygonx1 , y1 , x2 , y2 ... xn , yn , x1 , y1

It should be noted that when defining a polygon, the final pair of points should be the same as the first pair of points, to close the object. AREAs within a MAP section are parsed from top to bottom; that is, the first AREA from the top down within a client-side imagemap's referenced MAP into which the point the user clicked could fall, is the URL which gets taken.

For more definitive instructions, please see the section on the next page devoted to client-side imagemaps.

## <B>....</B>

ATTRIBUTES:
none

Causes text between the opening and closing tags to be rendered in a bolded face. <B> even changes the appearance of preformatted text (text contained within <PRE> tag).

This text is not bolded. This text is bolded.

Text cannot be bolded multiple times; surrounding a word with three sets of bold tags will not make it display any thicker text thann would a single set of bold tags.

## <BASE>

ATTRIBUTES:
HREF=url (required)

The BASE tag is used to denote the URL which should be used to dereference relative URLs for the given document. In other words, every URL link in an HTML document which does not begin with a scheme such as http:// or ftp:// will have whatever base URL is defined by the BASE tag, added to the front of it.

This comes in very handy when you'd like to move HTML files from one directory to another on a web server, or even from one server to another. If you used the BASE tag when you originally wrote the page, and used relative URLs throughout the rest of the page, you would not be forced to edit every link on the page by hand should you just move that one page.

For example, look at the figure to the right. If the web page (denoted by a gray box) in directory A were moved into directory B, but the elements of that web page (denoted by the red and green circles) remained in directory A, the web page would still be able to find its elements, provided the web page included a <BASE> tag which included the URL to get to directory A as its attribute.

In English: assume the web page in question here had, in its head section, the tag:

<BASE HREF="http://www.here.org/A/">
...and the elements were referenced in the document with relative URLs, such as:
<IMG SRC="REDCIRCLE.GIF">
When the web browser loads this page, it is going to add the BASE in front of each relative URL in the page, so our reference to the red circle is really:
<IMG SRC="http://www.here.org/A/REDCIRCLE.GIF">
If we were to move the web page to another directory, it would still know exactly where its files were... for the BASE tag is saying "All relative URLs in this page, are relative to this directory, referred to in the HREF attribute".

If the opposite were to happen (the elements of the page were moved to directory B), fixing the references would involve changing the "A" in the BASE tag's URL to a "B". Just that simple.

The <BASE> tag also allows us to be a little lazy, by entering as little of the URLs as necessary throughout the rest of the web page, while ensuring that we are pointing to a specific location. Without the <BASE> tag, when we moved the web page in our example into directory B, the web browser would try to find the page element "REDCIRCLE.GIF" in the current directory, and the result would be a "missing image" icon.

Be aware that even if you have a BASE tag in your header, any reference to an element or any link which uses a complete URL, will not add the URL found in the BASE tag in front. That is, if I had the two following lines inside of an HTML file:

<BASE HREF="http://www.here.org/A/">
...(many lines of html in here)...
<A HREF="http://rocknroll.com">
...the link to "rocknroll.com" would still point to "http://rocknroll.com", and not to the erroneous URL "http://www.here.org/A/http://rocknroll.com".

## <BASEFONT>

ATTRIBUTES:
SIZE=1 - 7 (required)

The <BASEFONT> tag changes the browser's default font size for normal and preformatted text, but not the font size for <Hn> headers.

This is text after setting the BASEFONT to 5.
This is text after setting the BASEFONT back to the default size of 3.

There is no closing tag for <BASEFONT>, because this tag simply sets the browser's default font to a different size for the document being rendered. If you wish to change the size of rendered text and intend to change it back, you should use the FONT tag instead.

## <BGSOUND>

ATTRIBUTES:
LOOP=n|INFINITE
SRC=url (required)

The <BGSOUND> tag is a Microsoft Internet Explorer extension which allows the addition of a background sound in the form of either a sampled audio clip, or a MIDI music file, specified by the URL given in the SRC attributes. The LOOP attribute can be used to repeat the sound either a specified number of times, or until the user moves to a different page (by setting the value of LOOP to INFINITE.

The <BGSOUND> tag has been referred to as the audio equivalent of the BLINK tag, because it gives viewers of the given web document no say in whether or not to hear your chosen sound file (unless, of course, they're using a browser other than Microsoft's Internet Explorer, in which case the tag is ignored).

## <BIG>....</BIG>

ATTRIBUTES:
=
=

<BIG> renders text between opening and closing fonts in a larger than usual typeface.

This text is big! This text is not.

ATTRIBUTES:
none

<BLINK> tag causes the text contained between the start and end tags to (what else) blink, if you are viewing the page in question with the Netscape browser. This effect is considered, in web design circles, to be only slightly less irritating than having your cranial capacity adjusted with a ball peen hammer.

In other words, don't use this tag. Ever. Unless you want to demonstrate what the clock on your VCR looks like:

12:00

## <BLOCKQUOTE>....</BLOCKQUOTE>

ATTRIBUTES:
none

The <BLOCKQUOTE> tag is used to specify passages of text which you wish to have indented, when rendered by the browser. Regular formatting tags still apply within blockquoted passages, so you may format emphasis in the blockquoted passage, like so:

..."and at this point, I turned to her, and asked her name. "Chelsea", she replied in a soft voice, almost too sotto voce to be heard. Surely she would know the way to the station from here... and surely, we would make our train on schedule! Once again, the game was afoot!
-Not Sir Arthur Conan Doyle

Formatting tip: When quoting passages, centering the author's name under the quoted passage looks generally better than left-flush formatting.

## <BODY >.....</BODY>

ATTRIBUTES:
BACKGROUND=url
BGCOLOR=color
BGPROPERTIES=fixed
CLASS=n pixels
ID=n pixels
LEFTMARGIN=n pixels
STYLE=stylesheet properties
TEXT=color
TOPMARGIN=n pixels

The <BODY> tags are used to contain the displayable elements of your web page. The closing tag, </BODY>, should be the last thing in your document, unless you use the optional <HTML> tag pair, in which case the final thing in your document would be a </HTML> tag.

<BODY> has more than its fair share of attributes which can be incorporated into the opening tag. These include several items which accept colors as arguments; we'll list these first for the sake of simplicity.

The attributes BGCOLOR, TEXT, LINK, VLINK, and ALINK can all accept any of sixteen named colors, or a hexadecimal color number, as described below. BGCOLOR sets the background color of the document, while the TEXT attribute is used to set the default font and line color for rendering the page. The LINK and VLINK attributes set the colors of unvisited and visited hypertext links on the page, respectively, while the ALINK attribute is used to set the color which a link is colored at the moment a user clicks on it.

The BACKGROUND attribute is used by Netscape's Navigator and Microsoft's Internet Explorer to fill the background of a page with an image, instead of a solid color. The image need not be large, either; small images will be repeated, or tiled, to fill the background of the browser's window. Microsoft additionally has a BGPROPERTIES tag which currently has only one possible value; setting BGPROPERTIES to FIXED will make the background image stay motionless when scrollbars are used, giving the effect that the elements on the page are "floating" above the background. This effect is only visible, as mentioned, with Internet Explorer.

Microsoft also has five additional attributes for the BODY tag supported only by their browser. LEFTMARGIN and TOPMARGIN allow you to specify how many pixels from the top and left edges of the browser window you wish to have text begin displaying. This, at least, seems to allow for some modifications to HTML layout; due to the vast differences in display hardware, though, the value of a tweak of this nature is questionable.

The CLASS attribute, according to Microsoft, "specifies the class to which the document belongs". I can find no other mention of what this attribute is used for, nor do any pages on Microsoft's own site appear to use it. Likewise, the ID attribute, which Microsoft added to allow for the addition of a unique "ID Number" to be added to each document; no one, including Microsoft, seems to be using this tag. Perhaps this was added by Microsoft for purposes of future development.

Microsoft also adds a STYLE attribute to the <BODY> tag; this implementation of the technology known as "Cascading Style Sheets" (or CSS) is, according to Microsoft, following a defined standard. (In reality, the Microsoft version of CSS was released two months before the accepted standard, which was produced by the W3 Consortium). If you are curious, you can read up on the technical specs for both the Microsoft's CSS , and the W3 Consortium CSS Recommendation; Style sheets allow tight control over how items such as <Hn> headers are rendered, how many pixels of space are left after paragraphs, and that sort of thing. This is definitely for Type-A Personalities, only.

### BACKGROUND IMAGES

Using JPEGs for background images is a plus. First of all, they are smaller files... usually much smaller, up to one tenth the filesize. Secondly, they offer better image quality over GIFs for photographic images. Third, every browser out which accepts background images, is also capable of handling JPEGs. This seminar has a detailed discussion on image formats.

### COLORS

Colors for these attributes are either one of sixteen predefined colors, or may be specified as hexadecimal numbers, discussed below the following table. The predefined color names (and the hexadecimal numbers they stand for) were chosen to match the Microsoft Windows 3.1 standard pallete, and are:

 Black = "#000000" Green = "#008000" Silver = "#C0C0C0" Lime = "#00FF00" Gray = "#808080" Olive = "#808000" White = "#FFFFFF" Yellow = "#FFFF00" Maroon = "#800000" Navy = "#000080" Red = "#FF0000" Blue = "#0000FF" Purple = "#800080" Teal = "#008080" Fuchsia = "#FF00FF" Aqua = "#00FFFF"

Specific colors can also be entered in the form "#RRGGBB", which are two-digit hexadecimal numbers for red, green, and blue color values. This means that the colors are specified by how much red, green, and blue they contain, and that the value for each of these three colors is a hexadecimal number, from 00 to FF.

If you're unfamiliar with hexadecimal numbers, here's a quick intro: Hexadecimal (or hex, for short) are numbers in the base 16 counting system. We're used to seeing base 10 numbers, but computers use hexadecimal instead, because computers understand the concept of powers of two (16 is two to the fourth power, or 2x2x2x2). In any case, the "numbers" in the hex counting system are:

0 1 2 3 4 5 6 7 8 9 A B C D E F

Therefore, if you're using two-digit hex numbers, the lowest number is specified by 00, and the highest you can count is FF. Try playing with the bgcolor value on a test page, to see what different values look like.

### Guaranteeing Colors

Netscape and Microsoft's Internet Explorer use a standard palette of 216 colors equally spread over the red, green, and blue color tables. Why the magic number 216? Well,because the lowest common denominator on machines which can display color is generally 256 colors, and 216 is the largest number below 256, which is a power of three: 6x6x6.

If you split up each of the red, green, and blue hexadecimal values into sixths of their maximum value, you get 216 possible colors, with values for their component colors stepped in increments of 33 hex. This is often known as the "color cube"; these 216 colors are guaranteed to display the same on a 32 million color IBM compatible computer's display, as on a 256 color Macintosh computer. Therefore, it behooves you to count your hexadecimal color numbers off in steps of 33, if you decide to specify colors this way (00, 33, 66, 99, CC, FF).

Overview on colors and background images
Bringing these two together... if I wished to use an image file named fish.jpg as a background pattern, and I wanted the text to be white and the links to be a medium blue-green, I might end up with body tags that looked like this:

<BODY background="fish.jpg" text=white links=#0099CC>
(Body text goes here...)
</BODY>
Under the HTML 3.2 standard, the <HTML>, <HEAD>, and <BODY> tags are implicit, and considered to be optional. However, when trying to control document colors and/or background images, HTML authors will still want to use a <BODY> tag, as the only other method for gaining such control over content is through the use of Cascading Style Sheets, which aren;t quite as simple as defining document colors through the <BODY> tag.

Due to this, and the lack of definitive purpose for the <HEAD> and <HTML> tags, this author thinks it likely that the <BODY> tag will remain a staple of the HTML standard, while the latter two might well fade into obscurity.

## <BR>

ATTRIBUTES:
CLEAR=left|right|all

Used to provide line breaks within body text. A line break differs from a paragraph break, in that paragraph breaks create whitespace after the line with the break. an example of the difference:

This text has a line break
between the two lines of text.

There is a paragraph break between the line above and this one.

Once you see the difference visually, it's pretty easy to decide which you need to use in any circumstance.

The CLEAR attribute allows you to specify that the browser should stop rendering text until it reaches a a point clear on the left side, the right side, or both sides, of floating images.

## <CAPTION>....</CAPTION>

ATTRIBUTES:
ALIGN=top|bottom

This tag is used to define a caption for an HTML table, rendered either above or below the table. Here are examples of both:

 Data Data Data Data
 Data Data Data Data
Caption text is rendered in the standard browser typeface and size.

## <CENTER>....</CENTER>

ATTRIBUTES:
none

<CENTER> aligns any contained elements in the the middle of the available width of the screen. If objects are present on the left or right side of the layout (a floating image or a floating table, for example), the elements to be centered will be rendered centered between the floating object and the opposite margin, or directly between the floating ojects on both sides, if two floating objects exist.

Originally developed by Netscape as an extension to provide a desired layout feature which was not present in HTML, the <CENTER> tag has been oficially defined in the HTML 3.2 standard. A note to this definition, however, labels the <CENTER> tag as simply being a shorthand method of writing <DIV align=center>.

## <CITE>....</CITE>

ATTRIBUTES:
none

The citation format. This is a logical formatting tag, which was created to allow citations to be set in HTML code. The reason for using the <CITE> style instead of physical tags which might provide the same appearance would be to allow computer programs to easily pull citations out of HTML documents.

EXAMPLE: See Wahlers, Moyer, and Wallinksi: Amer Journ Psych IV:3:1995

## <CODE>....</CODE>

ATTRIBUTES:
none

The program code format. This is a logical formatting tag, which was created to allow snippets of computer programs to be set in HTML code. The reason for using the <CODE> style instead of physical tags which might provide the same appearance would be to allow computer programs to easily pull such excerpts out of HTML documents.

EXAMPLE: printf("%s is your word.\n",\$usersWord);

## <COL>

ATTRIBUTES:
ALIGN=left|right|center
SPAN=n

<COL> is a Microsoft-only tag, for controlling the layout of tables in HTML. The only attributes it takes are an ALIGN option for the horizontal alignment of text within cells, and an optional SPAN option, which allows you to specify that the alignment being given should apply to n consecutive columns.

The idea, according to Microsoft, was to save users from having to add alignment tags to multiple rows worth of tables, while allowing for more control over the rendering of borders; COLGROUPs are drawn with a slightly heavier border around each group. In order to use the

A layout for Internet Explorer using <COL> and <COLGROUP> tags might look like:

 
Column One, Group One Column Two, Group One Column One, Group Two Column Two, Group Two
 As rendered under Internet Explorer 3.01 As rendered under Netscape Navigator 3.01
As this is only supported by one browser, it would be best to avoid this tag in favor of the accepted standard table definition tags, as defined by the HTML 3.2 Standard.

## <COLGROUP>

ATTRIBUTES:
HALIGN=left|right|center
SPAN=number of columns
VALIGN=top|bottom|middle
WIDTH=n pixels

The <COLGROUP> tag is used only by Microsoft's Internet Explorer, to define how columns within a table (specified with the COL tag) should be grouped together for the purposes of display. Please see the discussion for the COL tag for the syntax and an example of how this affects table rendering. <COLGROUP> does not have a closing tag.

<COLGROUP> has four attributes at this time. The HALIGN attribute allows you to specify how text in the cells belonging to the column group are horizontally aligned, while VALIGN does the same for vertical alignment. SPAN sets the number of consecutive columns that are in the group, and WIDTH sets the pixel or percentage width (use n or n%) that the column group will occupy in the table.

## <COMMENT>....</COMMENT>

ATTRIBUTES:
none

Provided solely for backwards-compatibility, the <COMMENT>...</COMMENT> tags were originally used to denote sections of HTML documents which would not be rendered onscreen by browsers, but which would still appear in the document's source. Comments are better served by using the SGML comment tags, which take the form:

<!-- comment text -->

If you are aware of where the <COMMENT>...</COMMENT> syntax originated, please contact the author of this document.

## <DD>....</DD>

ATTRIBUTES:
CLASS=type
ID=unique id
STYLE=style sheet properties

The <DD> tag is used in definition lists (see DL) to specify definition data. Browsers usually render definition data items, if included inside a definition list, indented slightly from the right.

This, for example, is a sentence enclosed in <DD>...</DD> tags, enclosed in a <DL> list.

<DD> is most useful when used in conjunction with definition terms; you may also wish to read about the definition term markup tag, DT.

Microsoft adds three proprietary attributes to this list creation element; CLASS can be used to specify a class type to which the list belongs, ID can be used to provide a document-unique identifier for the list, and STYLE allows the addition of stylesheet specifications, following Microsoft's format.

## <DFN>....</DFN>

ATTRIBUTES:
none

The <DFN>...</DFN> tags are used to surround an item being defined for the first time. This usually does not change the rendering of text in most browsers, but provides a logical distinction for programs which parse HTML documents looking for definitions. For example:

Kiwi fruit are not actually a fruit, but the world's largest berry.

Note: The above text was intentionally indented and altered in appearance to represent the fact that it was example text; the browser would not otherwise have rendered the example any differently than starndard text.

## <DIR>....</DIR>

ATTRIBUTES:
COMPACT
CLASS=CLASS TYPE
ID=unique value
STYLE=style attributes

The <DIR>...</DIR> tags are used to specify a "directory" list of items, each less that 20 characters, which should be rendered in multiple columns. Most browsers ignore the HTML 3.2 specification, and render such lists in single columns.

Individual items in a <DIR> list must be specified with the <LI> list item tag. A sample <DIR> list looks like this:

• Video
• Still Images
• Fine Art
• Audio Files
• The attribute COMPACT, is used to denote that a compacted, minimalized form of the <DIR>...</DIR> listing should be used, if possible.

Microsoft adds three proprietary attributes to this list creation element; CLASS can be used to specify a class type to which the list belongs, ID can be used to provide a document-unique identifier for the list, and STYLE allows the addition of stylesheet specifications, following Microsoft's format.

## <DIV>....</DIV>

ATTRIBUTES:
ALIGN=left|right|center
CLASS=class type
ID=unique value
LANG=ISO language code
NOWRAP

The <DIV>...</DIV> tags can be used to logically subdivide an HTML document into sections. Opening a <DIV>....</DIV> section automatically closes any open <P>...</P> section; that is, if you start a division, the browser will insert a line break, and then begin rendering the <DIV>...</DIV> section.

The ALIGN attribute allows the text within a division to be justified to the right or centered, and the LANG attribute allows specification of a two-character language code, as listed in the ISO 639 standard for tagging SGML documents with language identifiers. NOWRAP specifies that the text in the delineated section should not be automatically wrapped, but should extend as far across the right margin as needed. As in other instances, Microsoft's CLASS attribute can be used to specify what media type the division contains (text/html being the default).

## <DL>....</DL>

ATTRIBUTES:
COMPACT
CLASS=class type
ID=unique value
STYLE=style properties

The <DL>...</DL> tags are used to define a definition list, in which definition terms and definition data (<DT> and <DD>) tags are used to layout a list of left-justified terms, with indented definitions falling below each.

Orphan
A web page which is no longer linked to by other pages.
Widow
A web page whose owner has gone beyond.
Web Muffin
A web page of questionable value, approached with a stern seriousness not befitting its topic.

The COMPACT attribute specifies that a minimalistic version of the definition list should be rendered to save space, if possible. Microsoft's CLASS attribute allows HTML authors to specify a class type which relates to the list, the ID attribute allows the list to be tagged with a unique identification marker (unique to the document), and the STYLE attribute allows the addition of stylesheet specifications, following Microsoft's format.

## <DT>....</DT>

ATTRIBUTES:
CLASS=type
ID=unique id
STYLE=style sheet properties

The <DT> tag is used in definition lists (see DL) to specify a definition term (the word you wish to define). Browsers usually render definition terms, if included inside a definition list, as left-justified text, followed by a <BR> line break.

<DD> is most useful when used in conjunction with definition data; you may also wish to read about the definition data markup tag, DD.

## <EM>....</EM>

ATTRIBUTES:
none

The <EM>...</EM> tags instruct browsers to render the enclosed text in an emphasized manner; most graphic browsers do this by italicizing said text.

This text is emphazized. This text is not.

<EM> is a logical formatting tag.

## <EMBED>

ATTRIBUTES:
SRC=url
AUTOSTART=true|false (audio only)
ALIGN=top|bottom|center|baseline|left\right|texttop|middle|absmiddle|absbottom
HEIGHT=n
WIDTH=n
LOOP=n|true|false
STARTTIME=minutes:seconds
ENDTIME=minutes:seconds
VOLUME=0-100
PALETTE="#rrggbb|#rrggbb" (foreground|background)
UNITS=pixels|en (pixels|half point size)
CONTROLS=console|smallconsole|playbutton|stopbutton|volumelever (audio only)
HIDDEN=TRUE
MASTERSOUND=unique name (audio only)
CONTROLLER=true|false (video only)
LOOP=true|false|palindrome (video only)
PLAYEVERYFRAME=true|false (video only)
HREF=url (Quicktime/Quicktime VR only)
TARGET=frame
PLUGINSPAGE=url
AUTOPLAY=true|false (Quicktime)
PAN=fixed number (Quicktime VR)
TILT=fixed number (Quicktime VR)
FOV=fixed number (Quicktime VR)
CORRECTION=none|partial|full (Quicktime VR)

<EMBED> is used primarily by Netscape to insert multimedia objects into HTML layouts (Microsoft's Internet Explorer uses the OBJECT tag instead). The <EMBED> tag was originally conceived to handle audio, video, VRML, Quicktime video, and Quicktime VR elements, but any object which Netscape can understand (either natively or through the use of plug-ins) can be embedded.

As such, the attributes for the <EMBED> tag can be whatever parameters the embedded object requires. The listing given here is fairly thorough for most objects one might wish to embed, but there is no limit to the possible parameters you will find in <EMBED> tags.

 SRC: The URL of the object being embedded AUTOSTART: If set to TRUE, object wll begin running/playing when loaded. If set to FALSE, the object will not play automatically. The default is FALSE. ALIGN: The alignment of the object with its neighboring objects. HEIGHT: How many pixels tall the object (or for sounds, the console) will be WIDTH: How many pixels wide the object (or for sounds, the console) will be LOOP: Sets the item up to play once (false), a certain number of times (n), or continuously.(true), STARTTIME: how many minutes and seconds into a sound to begin playback from ENDTIME: How far into a sound playback should cease, also in minutes and seconds VOLUME: For sounds, how loud to set the inital volume, between 0 and 100 PALETTE: Allows setting of a foreground and background color for embedded object controls UNITS: Allows the setting of height/width measurement units, to pixels or half-points CONTROLS: Allows specification of what, if any, console controls are visible for audio objects HIDDEN: If set to true, the object will not be rendered. MASTERSOUND: Allows naming of console control groups, so that multiple controls can be used to manipulate the same sound. CONTROLLER: For Quicktime objects, allows the control strip to be hidden LOOP: Allows Quicktime objects to be looped, or even rolled back and forth PLAYEVERYFRAME: Forces every frame of Quicktime objects to be displayed, instead of skipping frames to keep key frames synched with audio HREF: Source URL for Quicktime objects TARGET: Specifies which frame or window an object should be loaded into PLUGINSPAGE: Allows specification of what web page to load if the Plug-In needed to handle an object is not available on a user's machine AUTOPLAY: Allows Quicktime objects to automatically start after loading PAN: Specifies the initial pan angle, in degrees, of a Qucktime VR movie. TILT: Specifies the initial tilt angle, in degrees, of a Qucktime VR movie. FOV: Allows specifitcation of the initial Field of View angle, in degrees, of a Qucktime VR movie. CORRECTION: Allows image correction for Quicktime VR panoramas and objects to none, partial, or full.

Again, these are only the most common attributes for the <EMBED> tag, taken from the LiveAudio, LiveVideo, Quicktime, Quicktime VR, and Live3D (VRML) basic objects. Other objects can and will require different attributes. (The key concept here is that the attributes are matched to the type of object being embedded).

## <FONT>....</FONT>

ATTRIBUTES:
SIZE=[1-7] or +n/-n
COLOR=colorname|#rrggbb
FACE=font family name(s)

The <FONT>...</FONT> tags are used to change the current font's size, color, and/or face. The HTML 3.2 standard only allows changing of font colors and sizes; Netscape and Microsoft both add the FACE attribute, which allows you to specify one or more fonts for the browser to render text with, in a comma-separated list.

The SIZE attribute can either be set to a value from 1 to 7 (one being smallest, and 7 being largest), or can be bumped up or down with the use of values such as "+2" or "-1".

The COLOR attribute can either be one of the standard 16 "named" colors, or can be a specific value set by balancing red, green, and blue values in hexadecimal couplets, in the format #RRGGBB. For more information on how mix colors, and on the standard 16 named colors, please see the discussion of colors found in the discussion of the BODY tag.

This is size 3 text, rendered using the Verdana or Helvetica font (if available), in a lovely shade of green.

If the browser is unable to find the typefaces requested in the FACE attribute, the browser's default proportional face will be used.

## <FORM>....</FORM>

ATTRIBUTES:
ACTION=url
METHOD=get|post
ENCTYPE=application/x-www-form-urlencoded
ONSUBMIT=event
TARGET=window

The <FORM>...</FORM> tags are used to wrap the elements of a web-based form. These elements are defined by the INPUT, SELECT, and TEXTAREA tags.

Web forms are most frequently used to submit data for processing to CGI (Common Gateway Interface) programs residing on web servers, but they can also send their contents to a mailto: URL as well, or even have their contents handled by browser-specific scripting languages such as JavaScript or ActiveX Visual Basic controls. The ACTION attribute is used to specify where <FORM>...</FORM> data should be sent once the user is done entering their information.

The METHOD attribute is used to define which of two communications methods will be used to submit the data from the form to the resource listed in the ACTION attribute; these two methods are GET and POST. Information passed from a for to an ACTION using the GET method will pass their data along as part of the URL, while data passed according to the POST method will be placed on the standard input (STDIN), for whatever resource is listed in the ACTION attribute to read in.

The ENCTYPE is a recent addition to the <FORM>...</FORM> tag, designed to allow the uploading of files through forms. The default value for ENCTYPE is "application/x-www-form-urlencoded", but if you were to set the value of ENCTYPE to "multipart/form-data", whatever the ACTION points to would be able to extract multiple data segments, each headed up by a MIME header describing the content of that section. Due to the volume of data considerations when using the form-upload capability of HTML 3.2, form uploading is only possible if the METHOD being used is POST instead of GET.

For more information on <FORM>...</FORM> elements can be found under the discussions of the INPUT, SELECT, and TEXTAREA tags.

## <FRAME>

ATTRIBUTES:
SRC=url
ALIGN=left|center|right|top|bottom
FRAMEBORDER=1|0
NAME=target name
NORESIZE
SCROLLING=yes|no
MARGINHEIGHT=n
MARGINWIDTH=n

The <FRAME> tag defines a single frame in a FRAMESET, and allows the setting of attributes to control many different aspects of the rendering of frames.

The SRC attribute allows users to specify what URL to load in the frame being defined. The ALIGN attribute allows control over how the elements loaded into the given frame will be aligned within the frame margins. FRAMEBORDER allows for control over whether (1) or not (0) a border is rendered around the frame being defined. NAME allows the setting of a unique name for the given frame, so that URLs can be directed to that frame by use of the TARGET attribute of the link tag.

NORESIZE, if present, prevents the user from resizing the viewed frames, and the SCROLLING attribute can be set to yes or no, to either allow or disallow rendering of a scrollbar in the current frame. Additionally, Microsoft's Internet Explorer allows the setting of MARGINWIDTH and MARGINHEIGHT attributes, which determine how much of a gutter must be left between the edges of frames and their content.

## <FRAMESET>....</FRAMESET>

ATTRIBUTES:
COLS=column widths|*
FRAMEBORDER=0|1
FRAMESPACING=n
ROWS=row heights|*

The <FRAMESET>...</FRAMESET> tags are used to enclose groups of FRAME tags, which are then rendered in the spaces set up by the COLS and ROWS attributes. COLS and ROWS can both take comma-delimited lists of pixel or percentage widths or heights. The asterisk (*) can be used in place of any value in such a list, to specify that all remaning space not used by the other columns or rows being defined within the current <FRAMESET> should be placed into the row or column represented by the asterisk.

FRAMEBORDER can be set to 1 to specify that borders between columns and rows should be rendered, or set to 0 to specify that the borders should be invisible. The FRAMESPACING attribute is used to set a gutter of n pixels between frames.

<FRAMESET>...</FRAMESET> tags can be nested; FRAMESETS contained within other FRAMESETS inherit all of the attributes (excluding COLUMN and ROW attributes) from the surrounding ("parent") <FRAMESET>.

An example frames setup might look something like the following:

  Sorry, You need frames for this page.  The layout to the left would produce a page with frame dimensions like the image below.

ATTRIBUTES:
none

Used to define the head section of an HTML page, which usually includes the title of the page, as well as information about the author, and often comments which usually include the last date of revision.

Under the new HTML 3.2 standard, the <HTML>...</HTML>, <HEAD>...</HEAD>, and <BODY>...</BODY> tags are implicit, and considered to be optional.

## <HR>

ATTRIBUTES:
ALIGN=left|center|right
WIDTH=n pixels|percent
SIZE=n pixels
CLASS=class type
ID=unique value
COLOR=colorname|#rrggbb
STYLE=style attributes

The <HR> (horizontal rule) tag is used to render a horizontal line in a document. Inserting such a tag infers that the current paragraph will be automatically closed, and whitespace rendered both above and below the rule.

The WIDTH attribute accepts either a pixel width, or a percentage. Not specifying this attribute will result in a horizontal rule being drawn across the entire width of the browser's window. The ALIGN attribute allows control over where in the browser window partial-width rules are drawn. Specifying a value for SIZE, in pixels, sets the vertical width of the rule. Using the NOSHADE attribute instructs the browser to draw the rule as a solid line, instead of rendered eith three-dimensional shading (which is the default).

Microsoft's Internet Explorer also handles three added attributes. The CLASS attribute allows the setting of a class-type value for the rule, COLOR changes the stroke color of the current rule, and STYLE allows for the addition of attributes following Microsoft's Style Sheets implementation.

## <HTML>.....</HTML>

ATTRIBUTES:
none

Used to contain the whole HTML document. Defines the start and end of the entire page. When used, the opening tag needs to be the second line of your document (following your !DOCTYPE directive), and the closing tag must be the last thing in your HTML document.

Under the new HTML 3.2 standard, the <HTML>, <HEAD>, and <BODY> tags are implicit, and considered to be optional.

## <Hn>....</Hn>

ATTRIBUTES:
ALIGN=left|center|right
n=n (1-6)

This tag is used to define section headers. Your choice of header sizes runs 1 through 6, one being the largest and most emphasized, and 6 being the smallest and least emphazised of the headers. In practice, this is what they look like:

# Level 1: <h1>... </h1>

## Level 2: <h2>... </h2>

### Level 3: <h3>... </h3>

#### Level 4: <h4>... </h4>

##### Level 5: <h5>... </h5>
###### Level 6: <h6>... </h6>
Note that after each header, there is automatically included whitespace. If you wish to change font sizes and format text without this whitespace, use the FONT tag instead.

## <I>....</I>

ATTRIBUTES:
none

Causes text between the opening and closing tags to be rendered in an italicized face. <I> even changes the appearance of preformatted text (text contained within <PRE> tag).

This text is not italicized. This text is italicized.

Text cannot be italicized multiple times; surrounding a word with three sets of italicize tags will not make it display text any more skewed than would a single set of italicize tags.

## <IMG>

ATTRIBUTES:
ALIGN=top|middle|center|bottom|left|right|texttop|textbottom|absmiddle
ALT=text
BORDER=n pixels
HEIGHT=n pixels
HSPACE=n pixels of horizontal gutter
ISMAP
SRC=url
USEMAP=MAP section name
VSPACE=n pixels of vertical gutter
WIDTH=n pixels
CLASS=class type
DYNSRC=url to dynamic source
CONTROLS
ID=unique value
LOOP=n
START=start-event
STYLE=style properties
TITLE=text

The next page in this seminar is a complete discussion on how to use images in web pages. There are a lot of attributes available for the <IMG> tag; here is a synopsis of what they mean:

ALIGN allows for alignment of images with other page elements; setting this value to left or right will turn the image being displayed into a floating image around which text will be flowed.

ALT sets the alternate text, shown to text-mode browsers, and individuals browsing the web with images turned off.

BORDER sets the pixel width of the link-colored border which surrounds images used as hyperlinks (via the tag tag); setting this attribute to zero will make images used as links have no link-colored border.

HEIGHT tells the browser how tall the image is, in pixels. Setting this value to a number other than the actual pixel height of the image will cause the image to be scaled by most browsers. Setting both HEIGHT and WIDTH attributes will allow the browser to lay out the document before all of the image elements have been received from the network.

HSPACE sets a horizontal gutter of n pixels between the given image and other elements on the page.

ISMAP specifies that the image, if being used as a clickable link, points to a server-side imagemap); setting this attribute to zero will make images used as links have no link-colored border.

HEIGHT tells the browser how tall the image is, in pixels. Setting this value to a number other than the actual pixel height of the image will cause the image to be scaled by most browsers. Setting both HEIGHT and WIDTH attributes will allow the browser to lay out the document before all of the image elements have been received from the network.

HSPACE sets a horizontal gutter of n pixels between the given image and other elements on the page.

ISMAP specifies that the image, if being used as a clickable link, points to a server-side imagemap. When clicked on, image links with an ISMAP attribute will send the X and y coordinates the user clicked on back to the server when opening the imagemap link.

SRC is used to specify the URL at which the image to be displayed resides.

USEMAP can be set to the name of a MAP element within the current document. This means that the image references a client-side imagemap, and should be treated as a clickable link, even though it is not surrounded by an tag. See the AREA and MAP tags for more information, or the discussion on the next page of client-side imagemaps. VSPACE sets a vertical gutter of n pixels between the given image and other elements on the page.

WIDTH tells the browser how widethe image is, in pixels. Setting this value to a number other than the actual pixel width of the image will cause the image to be scaled by most browsers. Setting both HEIGHT and WIDTH attributes will allow the browser to lay out the document before all of the image elements have been received from the network.

Microsoft has several Internet Explorer specific tags, as well; these are used as follows:

CLASS can be set with the class type of the curret image object.

DYNSRC can be given a URL as its value, which will let Inernet Explorer render a video clip or VRML scene within the image frame, instead of a static picture. See the OBJECT and EMBED tags for more information on video oobjects.

CONTROLS will place a control panel under the image frame, if the current object is a DYNSRC video clip.

ID can be set to be a document-specific unique value, which uniquely dentifies the image to the rest of the document.

LOOP can be set to let DYNSRC images loop a specified number of times, or even set to infinite to allow continuous repeating.

START can be set to specify that a DYNSRC video clip or VRML scence should start being rendered; this value can be set to fileopen, which will play the file as soon as it is completely loaded into the browser, or mouseover, which will play the clip or scene when the user moves their mouse over the image frame.

STYLE can contain style sheet elements, following Microsoft's style sheet format.

TITLE can be used to give images a title, referenceable by Internet Explorer from the rest of the document.

## <INPUT>

ATTRIBUTES:
ALIGN=top|middle|bottom|left|right
CHECKED
MAXLENGTH=n
NAME=name
SRC=url
VALUE=value
TYPE=input type
SIZE=size
CLASS=class type
ID=unique value
NOTAB
onBlur=event
onChange=event
onClick=event
onFocus=event
onSelect=event
TABINDEX=n
TITLE=text

<INPUT> elements are one of the building blocks of web-based forms. For more information on how to set up the superstructure for an HTML form, please see the FORM tag. You will also want to read about the SELECT and TEXTAREA form elements.

There is a large number of attributes associated with <INPUT> elements:

ALIGN determines how the <INPUT> element lines up with neighboring elements within the HTML document.

CHECKED is used to indicate that the <INPUT> element in question, if a checkbox or radiobutton type of form element, should be checked off.

MAXLENGTH specifies the maximum number of characters allowable in text, password, and file input elements.

NAME specifies what the input element benig defined is named; this is especially handy for groups of radiobuttons, of which only one item within the same form may be checked at a time.

SRC specifies the URL to be used as a background image for input elements of the type image.

VALUE specifies the default value of the element being defined. For SUBMIT and RESET buttons, setting the value to a text string will display that string on the button instead of the words "submit" or "reset".

TYPE determines which, out of nine possible choices, type of input element is being defined. The choices are:

 HIDDEN: nothing would be rendered here Checkbox: Radio: Text: Password: Submit: Reset: File: Image:

SIZE determines how wide input fields are rendered in the browser window.

In addition, Microsoft's Internet Explorer interprets several addiditional attributes: CLASS can be set to theclass type for this object, ID can be set to an identifier unique to this document, NOTAB specifies that the current field will not be cycled-to when the user is moving from field to field in the form with the tab key. The onBlur attribute can be set to an action to take when the cursor moves out of the input field being defined, onChange can be set to an action to take when the field being defined is changed, onClick when the field is clicked, onFocus when the pointer or cursor moves into the field being defined, and onSelect can be set to an action to take when the element being defined becomes selected (such as a radio button or checkbox).

The Microsoft attributes continue with TABINDEX, which, when set to a numeric value, will reflect the order, compared to other input elements, that this field will be reached when the tab key ibeing used to move from field to field. Finally, TITLE can be used to give the element and advisory title.

If you are developing web-based forms, be sure to check in on the FORM tag. You will also want to read about the SELECT and TEXTAREA form elements.

## <ISINDEX>

ATTRIBUTES:
ACTION=url
PROMPT=text

This tag is used to reference a page which is a searchable index; including this tag will place a text entry field at the location of this tag, which will prompt the user by placing the PROMPT text on the Submit button, and give its data over to the URL specified in ACTION.

## <KBD>....</KBD>

ATTRIBUTES:
none

Logical style used to represent text which would be typed at a keyboard by a user. Usually rendered in a monospaced font, and does not insert breaks of any kind when used.

This is a sample of KBD data.

## <LI>....<LI>

ATTRIBUTES:
TYPE=style
VALUE=n
CLASS=class type
ID=unique value
STYLE=style attributes

Used to specify individual list elements, belonging to ordered (OL), unordered (UL), definition (DL), directory (DIR), deprecated definition (DFN), and menu (MENU) lists.

The TYPE attribute is used for ordered lists, and can be set to A to use large letters, a to use small letters, I to use large Roman numerals, i to use small Roman numerals, or 1 to use arabic numerals. VALUE can be used to change the count value in an ordered list.

In addition, Microsoft's Internet Explorer interprets CLASS, which can be set to the class type for this list element, ID can be set to an identifier unique to this document for this element, and the STYLE attribute allows the addition of style sheet specifications, following Microsoft's format.

ATTRIBUTES:
HREF=url

The <LINK> tag has a wide variety of uses, but the general gist of its purpose is to establish a logical link between this document and other documents and/or objects. The <LINK> tag carries the same attributes as the <A> tag, but allows the addition of special relationships, expected to be used for document-level toolbars. Please note that while the methods associated with the <LINK> tag have yet to be used by any source known to the author of this site, there always exists the possiblity that this tag will indeed become implemented.

The LANG, DIR, and CHARSET directives in association with the <LINK> tag are suggested additions which are likely to be added to the HTML specifications, and so are included here. They are being discussed as part of the Internet Engineering Task Force's Internet Draft i18n. The possible values for the different entities possible in the <LINK> tag are as follows:

HREF
a standard format URL, which referes to the HTML document or the object to which this link is being defined.
TITLE
an "advisory title", which, assuming the <LINK> tag eventually gets used for document-level toolbars, might appear in a help window generated when the user moved a pointer over the link button generated by this reference. The TITLE attribute can also be used to give a name to an external stylesheet, as referenced in the W3 Consortium documents on Cascading Style Sheets.
REV
The relationship which the entity referred to in HREF has with this document. Suggested values for REV include Home, ToC, Index, Glossary, Copyright, Up, Next, Previous, Help, Bookmark, UseGlossary, Annotation, Reply, Embed, Precedes, Subdocument, Present, Search, Supercedes, History, Made, Owns, Approves, Supports, Refutes, Includes, and Interested.

A document which includes   <LINK REV="Made" HREF="mailto:mhazen@fcs.uga.edu"> in its head has the attribute of being Made by the entity reachable via the URL mailto:mhazen@fcs.uga.edu (which is a viable URL for the author of this seminar).

REL
The relationship which the this document has with the entity referred to in HREF. Suggested values for REV include Home, ToC, Index, Glossary, Copyright, Up, Next, Previous, Help, Bookmark, UseGlossary, Annotation, Reply, Embed, Precedes, Subdocument, Present, Search, Supercedes, History, Made, Owns, Approves, Supports, Refutes, Includes, and Interested.
LANG
This is currently being proposed as part of the IETF's Internationalization work as referenced in Internet Draft i18n. LANG, as proposed, will consist of a two character reference to one of the 136 languages specified in the International Standards Organization document iso639a.
DIR
This is currently being proposed as part of the IETF's Internationalization work as referenced in Internet Draft i18n. DIR can have one of two values, LTR for languages which are to be rendered from left to right, and RTL for languages requiring right to left rendering (such as arabic). No provision has yet been determined for languages which are natively rendered in top to bottom fashion (such as many Indo-Asian languages).
CHARSET
This is currently being proposed as part of the IETF's Internationalization work as referenced in Internet Draft i18n. CHARSET will take the value of an International Standards Organization (ISO) character set designation. The standard character set in use is ISO_8859-1, also known as LATIN 1.

A common use of the <LINK> tag would be to reference the current document as having been "made" by a particular person. Sample HTML code for such a reference would be:

...while using the <LINK> tag to specify that this document supercedes an earlier document would be:
The <LINK> tag is also used as the referencing element in the ongoing Cascading Style Sheets, in order to link an external style sheet (one referenced by the URL listed in the HREF attribute).

## <LISTING>....</LISTING>

ATTRIBUTES:
none

Deprecated tag which listed text in fixed-width type. Replaced more or less by <pre>.

## <MAP>....</MAP>

ATTRIBUTES:
NAME=name

Specifies a collection of AREA tags to be used as a client-side imagemap.

<map name="IMAGEMAP">
<area shape="rect" coords="18,18,82,80" href="square.html">
<area shape="circle" coords="127,48,31" href="circle.html">
<area shape="polygon" coords="232,78,303,78,263,14,232,76"
href="triangle.html">
</map>


## <MARQUEE>....</MARQUEE>

ATTRIBUTES:
ALIGN=left|center|right|top|bottom
BEHAVIOR=marquee type
BGCOLOR=color
DIRECTION=scroll direction
HEIGHT=n
HSPACE=n
LOOP=n
SCROLLAMOUNT=n
SCROLLDELAY=n
VSPACE=n
WIDTH=n

Microsoft's Internet Explorer interprets this tag to create a scrolling marquee of text on the web page. The attributes are used as follows:

ALIGN specifies how the marquee should be aligned with neigboring page elements.

BEHAVIOR can be one of scroll, slide, or alternate. Scroll is a standard left-to-right continous scroll, Slide scrolls across the screen but pauses when the text touches the opposite margin, and alternate bounces the marquees back and forth between the borders.

BGCOLOR sets the background color for the marquee block.

DIRECTION can be set as left or right; the default is left, which means that text scrolls from the right towards the left.

HEIGHT can be set to the number of pixels high the marquee should be.

HSPACE sets a horizontal gutter of n pixels between the marquee and neighboring elements.

LOOP can be set to allow the scroll to repeat either n times, or infinite.

SCROLLAMOUNT should be set to the number of pixels to move the text with each successive redraw of the marquee.

SCROLLDELAY specifies the number of milliseconds between redraws of the marquee.

VSPACE sets a vertical gutter of n pixels between the marquee and neighboring elements.

WIDTH can be set to the number of pixels wide the marquee should be.

Now is the time for all good marquees to come to the aid of their country.
<MARQUEE DIRECTION=LEFT BEHAVIOR=SLIDE
SCROLLAMOUNT=5 SCROLLDELAY=100 WIDTH-450>
Now is the time for all good marquees to come
to the aid of their country.
</MARQUEE>


ATTRIBUTES:
COMPACT
CLASS=CLASS TYPE
ID=unique value
STYLE=style attributes

The <MENU>...</MENU> tags are used to specify a "menu" list of items, which should be rendered in a single column.

Individual items in a <MENU> list must be specified with the <LI> list item tag. A sample <MENU> list looks like this:

• Video
• Still Images
• Fine Art
• Audio Files
• The COMPACT attribute is used to denote that a compacted, minimalized form of the <MENU>...</MENU> listing should be used, if possible.

Microsoft adds three proprietary attributes to this list creation element; CLASS can be used to specify a class type to which the list belongs, ID can be used to provide a document-unique identifier for the list, and STYLE allows the addition of stylesheet specifications, following Microsoft's format.

## <META>

ATTRIBUTES:
NAME=meta name
CONTENT=meta content
CHARSET=character set
URL=

The <META> tag is used to include name and value pairs in an HTML document which describe the properties of the document. One of the most common name and value pairs is to associate the name of an HTML document's creator with the META identifier "Author", like so:

<META NAME="Author" CONTENT="Joe Webguru">


Another attribute of the <META> tag allows the sending of extra HTTP headers along with a document, when the document is distributed to clients from a web server; this is the HTTP-EQUIV attribute. A common use of this attribute is to send "Expires" headers, such as:

<META HTTP-EQUIV="Expires" CONTENT="Mon, 31 Mar 1997 12:00:00 EST">


This header is used by caching servers, to determine when to fetch a new copy of the document in question. Not all HTTP keaders can be sent along as HTTP-EQUIV codes; you may wish to consult a more detailed HTTP reference for more information HTTP-EQUIV headers.

## <MULTICOL>....</MULTICOL>

ATTRIBUTES:
COLS=n (required)
GUTTER=n
WIDTH=n

The <MULTICOL>...</MULTICOL> tag, a proprietary tag made my Netscape for the 3.01 release version of their browser, allows document elements to be flowed into multiple columns. This differs from columns in tables in that the <MULTICOL>...</MULTICOL> element automatically divides up the text to fit the given number of columns evenly.

There are three attributes associated with <MULTICOL>...</MULTICOL>. The first, COLS, can be set to tell Netscape how many columns to flow the given text elements into. This is a required attribute.

The second attribute, GUTTER, specifies how many pixels should be left between the columns. The default value for GUTTER is 10 pixels.

The third attribute, WIDTH, can be given a pixel width to make each column. All columns are equal in width with the <MULTICOL>...</MULTICOL> tag. Here's a sample of a three-column layout with a few added FONT tags, for those who can view it:

LOREM IPSUM DOLOR sit amet, consectetaur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprederit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum Et harumd und lookum like Greek to me, dereud facilis est er expedit distinct. Nam liber te conscient to ctor tum poen legum odioque civiuda. Et tam neque pecun modut est neque nonor et imper ned libidig met, consectetur adipiscing elit, sed ut labore et dolore magna aliquam makes one wonder who would ever read this stuff? Bis nostrud exercitation ullam mmodo consequet.

## <NOBR>....</NOBR>

ATTRIBUTES:
none

Text encapsulated by <NOBR>...</NOBR> tags is rendered without wordwrapping, however far past the right border of the browser window the text needs to extend before the closing </NOBR> tag is reached. This is a potentially useful concept to avoid letting things you would not want split across two lines, to get split; surrounding phone numbers with <NOBR>...</NOBR> tags would avoid spreading them across two lines.

By using the <WBR> tag, you can mark points within long stretches of <NOBR>...</NOBR> text at which the browser could insert a carriage return, if needed.

## <NOFRAMES>....</NOFRAMES>

ATTRIBUTES:
none

The <NOFRAMES>...</NOFRAMES> tags are used inside of a FRAMESET to provide content for browsers who do not support frames.

<FRAMESET>
<NOFRAMES>
</NOFRAMES>
</FRAMESET>


ATTRIBUTES:
=
=

## <OL>....</OL>

ATTRIBUTES:
COMPACT
TYPE=A|a|I|i|1
VALUE=n
CLASS=CLASS TYPE
ID=unique value
STYLE=style attributes

The <OL>...</OL> list creates ordered lists of items, each of which is numbered. The style of numbering can be chosen by setting the TYPE attribute to one of the following:

TYPE: Style:
1 1. 2. 3.
I I. II. III
i i. ii. iii.
A. A. B. C.
a a. b. c.

1. Video
2. Still Images
3. Fine Art
4. Audio Files

By including the COMPACT attribute in your list tag, you can request that the browser render the list in a slightly more compacted form; some browsers have been known to ignore this tag, however.

Microsoft adds three proprietary attributes to this list creation element; CLASS can be used to specify a class type to which the list belongs, ID can be used to provide a document-unique identifier for the list, and STYLE allows the addition of stylesheet specifications, following Microsoft's format.

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

## <PLAINTEXT>

ATTRIBUTES:
none

Deprecated tag originally used to denote that the rest of the page was to be ASCII text. Denoting the rest of a page as plaintext wasn't a great idea, since interpreting text as plain ASCII means tags aren't interpreted. There was therefore no closing tag like </plaintext>, so once you went plaintext, you couldn't get back.

The functionality of the <PLAINTEXT> tag has since been replaced, essentially, with the advent of the <PRE>...</PRE> tag, coupled with HTML escaped entities (also known as special characters).

## <PRE>

ATTRIBUTES:
WIDTH=n

Text between <PRE>...</PRE> tags will be display in the browser window just as it appears in its file, without word-wrapping, or whitespace compression. The exception to this is that HTML tags, with the exception of image tags and tags which change the face and size of the font, will be interpreted; this means that a paragraph surrounded by <PRE>...</PRE> tags which includes hypertext links, will be displayed in the browser with active links.

To keep from interpreting these HTML tags, the < and > symbols need to be converted to &lt; and &gt; HTML escaped entities (also known as special characters).

The WIDTH attribute does not wrap the given text; instead, it is used to give browsers an idea of how wide the text file is, so that more intelligent browsers can adjust their rendering to try and fit the preformatted text within the width of th browser screen.

## <STRIKE>....</STRIKE>

ATTRIBUTES:
none

The <S>...</S> tags are used to delimit text to be physically formatted as stricken-through (redlined).

This text is striken. This text is not.

The <S>...</S> tags were originally in the HTML 3.0 standard, is comprehended by most browsers, and may replace the current standard strikeout tags, <STRIKE>...</STRIKE> in future versions of HTML.

## <STRONG>....</STRONG>

ATTRIBUTES:
none

The <STRONG>...</STRONG> tags are used to delimit text to be logically formatted as "strongly emphasized".

This text is strong. This text is not.

## <SAMP>....</SAMP>

ATTRIBUTES:
none

The <SAMP>...</SAMP> tags are used to delimit text to be logically formatted as sample program output.

This text is sample text. This text is not.

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

## <SMALL>....</SMALL>

ATTRIBUTES:
none

The <SMALL>...</SMALL> tags are used to delimit text to be rendered in a slightly smaller than usual typeface.

This text it small. This text is not.

## <SPACER>

ATTRIBUTES:
TYPE=horizontal|vertical|block
SIZE=n
WIDTH=n
HEIGHT=n
ALIGN=left|right|top|bottom|middle

TYPE, SIZE, WIDTH, HEIGHT, and ALIGN The <SPACER> tag is used to add space between the elements of an HTML document. There are two ways to use the <SPACER> tag, as well; as a indenting spacer, and as an invisible image spacer.

In the first case, you might enter:

<SPACER TYPE=HORIZONTAL SIZE=40>

If your browser supports the <SPACER> tag, you might notice that the first line of this paragraph is indented to the right; that is what the <SPACER> tag, as seen above, does when used in indention mode.

Alternatively, the <SPACER> tag can be given values for its HEIGHT, WIDTH, and ALIGN attributes, and used to take up space invisibly, as if it were an image that is not there. This is the reason that this paragraph is narrower than normal; there is a <SPACER> tag before it with the following attributes:

<SPACER TYPE=BLOCK HEIGHT=120 WIDTH=240 ALIGN=LEFT>


Again, this is a Netscape-only tag at this point.

ATTRIBUTES:
=
=

## <STRIKE>....</STRIKE>

ATTRIBUTES:
none

The <STRIKE>...</STRIKE> tags are used to delimit text to be physically formatted as stricken-through (redlined).

This text is striken. This text is not.

## <STRONG>....</STRONG>

ATTRIBUTES:
none

The <STRONG>...</STRONG> tags are used to delimit text to be logically formatted as "strongly emphasized".

This text is strong. This text is not.

ATTRIBUTES:
=
=

## <SUB>....</SUB>

ATTRIBUTES:
none

The <SUB>...</SUB> tags are used to delimit text to be physically formatted as subscripted.

O2 + N = N2O2

## <SUP>....</SUP>

ATTRIBUTES:
none

The <SUP>...</SUP> tags are used to delimit text to be physically formatted as superscripted.

E = MC2

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

ATTRIBUTES:
=
=

## <TITLE>....</TITLE>

ATTRIBUTES:
none

Used to specify what the title of an HTML document is. Under HTML 3.2, this element is required.

<TITLE>A Very Neat Webpage</TITLE>


ATTRIBUTES:
=
=

## <TT>....</TT>

ATTRIBUTES:
none

The <TT>...</TT> tags are used to delimit text to be physically formatted as "teletype" or monospaced.

This is a monospaced font. This is not.

## <U>....</U>

ATTRIBUTES:
none

The <U>...</U> tags are used to delimit text to be physically formatted as undelined.

This is underlined. This is not underlined.

## <UL>....</UL>

ATTRIBUTES:
COMPACT
TYPE=disc|circle|square
CLASS=CLASS TYPE
ID=unique value
STYLE=style attributes

The <UL>...</UL> list creates unordered lists of items, each of which is bulleted. The style of bullet can be chosen by setting the TYPE attribute to disc, circle, or square.

• Video
• Still Images
• Fine Art
• Audio Files

By including the COMPACT attribute in your list tag, you can request that the browser render the list in a slightly more compacted form; some browsers have been known to ignore this tag, however.

Microsoft adds three proprietary attributes to this list creation element; CLASS can be used to specify a class type to which the list belongs, ID can be used to provide a document-unique identifier for the list, and STYLE allows the addition of stylesheet specifications, following Microsoft's format.

## <VAR>....</VAR>

ATTRIBUTES:
none

Logical typestyle used to delimit a variable or an argument to a command. document. For example, if I were typing out a seminar, and I needed to state a variable in a sentence such as "x will always be greater than x-1", I could do it with the <var>... </var> tag pair.

## <WBR>

ATTRIBUTES:
none

The <WBR> tag is used in the middle of passages of text formatted with the NOBR tag, to provide controlled places at which a carriage returns could be rendered, if necessary. It carries no attributes, and it is not guaranteed to affect the display of elements on the page.

## <XMP>....</XMP>

ATTRIBUTES:
none

This deprecated tag was usually used to show examples of things such as HTML source code, as it not only used a monospaced font and preserved the layout as typed into the HTML source, but it also disabled every tag except the </xmp> tag. This meant that you could include tags within a block of text, and they would have displayed on the screen instead of being taken literally as tags, and would also have been rendered in the same format as they are present in the HTML source code file.