Tag
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What it is
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When to use it
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<A>
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Anchor (most commonly a link)
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Vital. Use to create links in
content. Use the title attribute whenever the contents of the <a>…</a>
pair do not accurately describe what you’ll get from selecting the link.
Title attribute often displays as a tooltip in visual browsers, which may be
a helpful usability aid.
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<ABBR>
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Defines an abbreviation
|
Works in a similar way to <dfn>
and <acronym>, using a title attribute (displays a
tooltip in standard visual browsers). e.g. <abbr title=”Hypertext
markup language”>HTML</abbr>
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<ACRONYM>
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Defines an acronym
|
Works in a similar way to <abbr>
and <dfn>, using a title attribute (displays a tooltip in
standard visual browsers).
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<ADDRESS>
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Used for marking up a physical
(e.g. mailing) address
|
Not commonly used. Recommend
looking into microformats, which allow for more detail and interoperability.
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<APPLET>
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Inserts a Java applet
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The old way to insert a Java app.
Use <object> instead today.
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<AREA>
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Hotspot in image map
|
Avoid image maps where possible.
Occasionally necessary.
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<BASE>
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Specifies the base location of the
document.
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Use only when necessary. Adjusts
any relative links and paths within the document.
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<BASEFONT>
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Sets default font size
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Display info – never use it
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<BIG>
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Larger text
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Display info – never use it
|
<BLINK>
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Makes text blink
|
You go to hell if you use this
|
<BLOCKQUOTE>
|
Large quoted block of text
|
Use for any quoted text that
constitutes one or more paragraphs (note: should contain <p> tags as
well). Use <q> for quotations within a paragraph. Often used in
conjunction with <cite> to cite the quotation’s source.
|
<BODY>
|
Document body
|
Essential (unless you’re using
frames)
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<BR>
|
Line break
|
This is arguably display
information. Still in common use, but use with restraint.
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<B>
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Bold text
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Display info – never use it
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<BUTTON>
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Used for a standard clickable
button within a form
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Often better than <input
type=”button” /> or <input type=”submit” />, as it allows
you to assign different styles based on the HTML element alone, whereas
differentiating style based on the type of input is less well supported.
|
<CAPTION>
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Caption for a table: describes the
table’s contents
|
The correct way to assign a title
to a table
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<CENTER>
|
Centred block
|
Display info – never use it. Use <div>
or some other block-level tag with the style text-align:center instead
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<CITE>
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Defines a citation
|
Defines the source of a quotation
(in conjunction with content in <q> or <blockquote>
pairs).
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<CODE>
|
Defines an extract of code
|
Not commonly used. Similar to <pre>
tag, but collapses consecutive white spaces and line breaks in the source.
|
<COL>
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Identifies a particular column in
a table
|
Can be very useful. e.g. <col
class=”namecol”> can be applied to each first column in a series of
tables, then the width of each column may be set to be equal in the
stylesheet, overriding the table’s natural tendency to adjust its own column
widths to fit its contents.
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<DFN>
|
Definition of a term
|
Works in a similar way to <abbr>
and <acronym>, using a title attribute (displays a
tooltip in standard visual browsers).
|
<DIR>
|
Directory list
|
Now deprecated. Use a standard <ul>
or other list instead.
|
<DIV>
|
Division
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Specifies a logical division
within a document. Use it to separate or identify chunks of content that are
not otherwise distinguished naturally using other tags.
One of the most common HTML tags.
|
<DL>
|
Definition list
|
Contains one or more
definition-term / definition-description pairs.
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<DT>
|
Definition term
|
Used as part of a <dt></dt><dd></dd>
pair within a definition list (<dl></dl>)
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<DD>
|
Definition description
|
<EM>
|
Emphasis
|
Commonly used in place of the old <i>
(italics) tag to indicate emphasis (but less than <strong>)
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<FONT>
|
Font settings
|
Display info – never use it
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<FORM>
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Input form
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Essential for data input
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<H1>
|
Level 1 header
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Aim to have one H1 on each page,
containing a description of what the page is about.
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<H2>
|
Level 2 header
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Defines a section of the page
|
<H3>
|
Level 3 header
|
Defines a sub-section of the page
(should always follow an H2 in the logical hierarchy)
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<H4>
|
Level 4 header
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Etc. Less commonly used
|
<H5>
|
Level 5 header
|
Less commonly used. Only complex
academic documents will break down to this level of detail.
|
<H6>
|
Level 6 header
|
Less commonly used
|
<HEAD>
|
Document head
|
Essential. Contains information
about a page that does not constitute content to be communicated as part of
the page.
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<HR>
|
Horizontal rule
|
Display info with no semantic
value – never use it. “Horizontal”, by definition, is a visual attribute.
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<HTML>
|
|
Core element of every web page.
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<IMG >
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Show an image
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Vital. Always use the alt
or longdesc attributes when the image has content value
|
<INPUT>
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Input fields within forms
|
Vital. (I prefer to use <button>
for buttons and submit buttons though)
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<ISINDEX>
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Old type of search input
|
Not really used any more. Use <form>
instead.
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<I>
|
Italicised text
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Display info – never use it
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<KBD>
|
Keyboard input
|
Display info – never use it
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<LINK>
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Defines a relationship to another
document
|
Commonly used to reference
external stylesheets, but has other minor uses
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<LI>
|
List item
|
Specifies an item in an unordered
or ordered list (<ul> or <ol>)
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<MAP>
|
Client-side imagemap
|
May have occasional value, but
only use when absolutely necessary
|
<MARQUEE>
|
Makes text scroll across the
screen
|
See <blink>
|
<MENU>
|
Menu item list
|
Deprecated. Do not use. Use other
standard list types instead.
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<META>
|
Meta-information
|
Useful way to insert relevant
information into the <head> section of the page that does not need to
be displayed.
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<OL>
|
Ordered list
|
Type of list where the order of
elements has some meaning. Generally rendered with item numbers (best managed
with CSS).
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<OPTION>
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Selection list option
|
Vital for options within a
drop-down control.
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<PARAM>
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Parameter for Java applet
|
Used in conjunction with an <object>
or <applet> tag to pass additional setting information at
runtime.
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<PRE>
|
Preformatted text
|
Renders text in a pre-formatted
style, preserving line breaks and all spaces present in the source. May be
useful. (This one’s a paradox, as it is strictly display info that applies
only to visual browsing, but it’s still so commonly used and useful that I’m
hesitant to advise against using it.)
|
<P>
|
Paragraph
|
Only use to denote a paragraph of
text. Never use for spacing alone.
|
<Q>
|
Short quotation
|
Use for inline quotations (whereas
<blockquote> should be used for quotations of a paragraph or
more). Often used in conjunction with <cite> to cite the
quotation’s source.
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<SAMP>
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Denotes sample output text
|
Similar to the <code> tag.
Rarely used. Avoid.
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<SCRIPT>
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Inline script (e.g. JavaScript)
|
It’s better to have all scripts as
separate files than to write inline or in the <head> section,
however still has its uses.
|
<SELECT>
|
Selection list
|
A drop-down selector for a form.
|
<SMALL>
|
Smaller text
|
Display info – never use it
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<SPAN>
|
An inline span within text
|
Use to apply meaning (and style)
to a span of text that goes with the flow of content (whereas a <div>
tag is block-level and breaks the flow)
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<Strikeout>
|
|
Display info – never use it
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<STRONG>
|
Strong emphasis
|
Use this instead of the old <b>
tag.
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<STYLE>
|
CSS style settings
|
Normally used in <head>
section of a page. Try to use external stylesheets, to enable you to apply
different styles for different output media.
|
<SUB>
|
Subscript text
|
Arguably display info – recommend
using alternative tags (e.g. <cite>). May be required in some
academic uses, e.g. Chemical formulas.
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<SUP>
|
Superscript text
|
<TABLE>
|
Table
|
Use for repeated data that has a
naturally tabular form. Never use for layout purposes.
|
<TD>
|
Table data cell
|
A cell containing actual data. If
a cell actually contains a descriptor or identifier for a row or column, use
a <th> (table header) tag, not a <td>. This usually
applies to column headers (within a <thead>), column footers
(within a <tfoot>), as well as row headers (usually the first
cell in a row in the <tbody>).
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<TEXTAREA>
|
Multi-line text input area in a
form
|
Essential
|
<TH>
|
Table column or row header cell
|
May appear in a <thead>
(to denote a column header cell), <tbody> (to denote a row
header), and in <tfoot> (to denote a column foot cell, e.g. a
total)
|
<TBODY>
|
Indicates the main body of a data
table
|
It is always worth using this tag,
as well as using <thead> and <tfoot> where
appropriate.
Note that it is permissible to
have more than one <tbody>, <thead>, and <tfoot>
in the same table.
|
<THEAD>
|
The head section of a table
|
The place to put column header
cells (<th>)
|
<TFOOT>
|
The foot section of a table
|
Good place to put e.g. summary
data, such as totals. Note that it goes before the <tbody> tag!
|
<TITLE>
|
Document title
|
Essential
|
<TR>
|
Table row
|
Essential with tables
|
<TT>
|
“Teletype” – simulates typewriter
output
|
Similar to <pre>, except
that it collapses white space like normal HTML (whereas <pre> leaves
all consecutive white space intact). Avoid if possible
|
<UL>
|
Unordered list
|
Essential. Use for lists where the
order or items has no particular importance.
|
<U>
|
Underline text
|
Display info – never use it
|
<VAR>
|
Variable in computer code
|
Obscure tag, may only be useful in
academic documents. Avoid.
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