Tag Features by George Hernandez

!-- (HTML comment) | !DOCTYPE | a | abbr | acronym | address | applet | area | b | base | basefont | bdo | big | blockquote | body | br | button | caption | center | cite | code | col | colgroup | dd | del | dfn | dir | div | dl | dt | em | fieldset | font | form | frame | frameset | h1 | h2 | h3 | h4 | h5 | h6 | head | hr | html | i | iframe | img | input | ins | isindex | kbd | label | legend | li | link | map | menu | meta | noframes | noscript | object | ol | optgroup | option | p | param | pre | q | s | samp | script | select | small | span | strike | strong | style | sub | sup | table | tbody | td | textarea | tfoot | th | thead | title | tr | tt | u | ul | var

This page discusses features common to many of the HTML tags. Also included is the syntax I used in listing the HTML tags.

Tag Syntax

Here are general syntax rules that apply to all the tags:

Most of the tags have the same syntax. Notable exceptions the above syntax includes the structural SGML tags. Here are the two basic syntaxes:
```
<TagName> ContentEnclosedByTags  </TagName>
<TagName />
```
Each tag may have one or more attributes whose values may be set. EG:
```
<h1 align="center">Welcome</h1>
```
Each tag may have one or more intrinsic events that can set for detection. EG:
```
<b onmouseover="DoThis()">Show Me</b>
```
Each attribute or intrinsic event may have one or more properties whose values may be set. EG:
```
<p style="font-size:5; color:#990000;">
```
There are several simple rules to make an HTML document a well formed XHTML document. These should be followed as much as possible in case the document is ever translated to an XHTML document.

Common Attributes

ACCESSKEY. Indicates a letter that can be used as a keyboard shortcut to put focus on the tag. This is typically ALT+AccessKey for PCs and CTRL+AccessKey for Macs. For Windows, the presence of an HTML accesskey takes precedence of application access keys. EG: If you put in an HTML accesskey of "h", then it is accessed by pressing "ALT+h" and the application's help menu is accessed by pressing "ALT" then "h". Applies to the following elements: a, area, button, input, label, legend, and textarea.
CLASS. A list of classes affecting the element. Applies to all elements except for: base, basefont, head, html, meta, param, script, style, and title.
DIR. The direction the text is read, i.e. either ltr or rtl.
DISABLED. Indicates a disabled control. Applies to the following tags: button, input, optgroup, option, select, and textarea.
ID. An identifier for the element, unique on the page. Applies to all elements except for: base, head, html, meta, script, style, and title.
NAME. Usually identifies the item in question. The ID attribute is usually much clearer.
LANG. Identifies the ISO language used. See also my section on Language. Applies to all elements except for: applet, base, basefont, br, frame, frameset, iframe, param, and script.
STYLE. Inline CSS application. Applies to all elements except for: base, basefont, head, html, meta, param, script, style, and title.
TABINDEX. A number between 0 and 32767 which indicates the position of the current item in the tabbing order. This attribute applies to the following tags: a, area, button, input, object, select, and textarea.
TARGET. The name of the frame where a document will be opened. This is is used by <a>, <link>, <area>, and <form>. The following frame names are reserved and have special meaning:
- _blank. The browser should load the designated document in a new, unnamed window.
- _self. The default. The browser should load the document in the same frame as the element that refers to this target.
- _parent. The browser should load the document into the immediate FRAMESET parent of the current frame. This value is equivalent to _self if the current frame has no parent.
- _top. The browser should load the document into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent.
TITLE. Information about the element. This not to be confused with the <title> tag which is for the whole document. The value of TITLE is commonly rendered as a "tool tip" (a message that pops up when the cursor is held over an object) or as audio (for audio browsers). Applies to all elements except for: base, basefont, head, html, meta, param, script, and title.
TYPE. This has different meanings depending on the tag!
VALUE. This has different meanings depending on the tag!

Common Intrinsic Events

Tag Stats

Tags	Start /End	Empty	Depr. /FP	DTD	Type
91	4 OO 13 / FF 15 / OO	13 EE	10 XX 8 / FP	11 LD 3 FD	13 SL 37 BL 43 TL

Note that there are 93 of the three types of tags because the <isindex> tag is both a SL and BL tag, and the <script> tag is both a SL and TL tag.

Tag Listings Syntax

Here is the syntax I used in listing the HTML tags:

[StartTag/EndTag][EE ][XX][FP]. [Description. ][TagGroup.]

Legend:

OO. Optional.
FF. Forbidden.
EE. Empty.
XX. Deprecated.
LD. Loose DTD,
FD. Frameset DTD.
FP. Not directly supported by Microsoft FrontPage.
SL. Structural Level.
BL. Block Level
TL. Text Level.

A DTD (Document Type Definition) is a document that defines an SGML compliant markup language. See also the SGML <!doctype> tag. Here are the three DTDs that are used in defining HTML 4.01:

Strict DTD. Formal HTML 4.01 without any deprecated tags.
Loose DTD, aka Transitional DTD. This is Strict DTD plus some of the tags that are deprecated.
Frameset DTD. This is Loose DTD but with the <body> tag replaced by the <frameset> tag.

Page Modified: (Hand noted: 2007-09-12 21:12:27Z) (Auto noted: 2007-11-17 06:40:25Z)