HTML Tags

N.B: Collected

> 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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Tag	What it is	When to use it
	Anchor (most commonly a link)	Vital. Use to create links in content. Use the title attribute whenever the contents of the … 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.
	Defines an abbreviation	Works in a similar way to and , using a title attribute (displays a tooltip in standard visual browsers). e.g. HTML
>	Defines an acronym	Works in a similar way to and , using a title attribute (displays a tooltip in standard visual browsers).
>	Used for marking up a physical (e.g. mailing) address	Not commonly used. Recommend looking into microformats, which allow for more detail and interoperability.
>	Inserts a Java applet	The old way to insert a Java app. Use instead today.
>	Hotspot in image map	Avoid image maps where possible. Occasionally necessary.
>	Specifies the base location of the document.	Use only when necessary. Adjusts any relative links and paths within the document.
>	Sets default font size	Display info – never use it
>	Larger text	Display info – never use it
>	Makes text blink	You go to hell if you use this
>	Large quoted block of text	Use for any quoted text that constitutes one or more paragraphs (note: should contain tags as well). Use for quotations within a paragraph. Often used in conjunction with to cite the quotation’s source.
>	Document body	Essential (unless you’re using frames)
>	Line break	This is arguably display information. Still in common use, but use with restraint.
>	Bold text	Display info – never use it
	Used for a standard clickable button within a form	Often better than or , 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 for a table: describes the table’s contents	The correct way to assign a title to a table
>	Centred block	Display info – never use it. Use or some other block-level tag with the style text-align:center instead
>	Defines a citation	Defines the source of a quotation (in conjunction with content in or pairs).
>	Defines an extract of code	Not commonly used. Similar to tag, but collapses consecutive white spaces and line breaks in the source.
Identifies a particular column in a table	Can be very useful. e.g.
>	Definition of a term	Works in a similar way to and , using a title attribute (displays a tooltip in standard visual browsers).
>	Directory list	Now deprecated. Use a standard or other list instead.
>	Division	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.
>	Definition list	Contains one or more definition-term / definition-description pairs.
>	Definition term	Used as part of a pair within a definition list ( )
>	Definition description
>	Emphasis	Commonly used in place of the old (italics) tag to indicate emphasis (but less than )
>	Font settings	Display info – never use it
>	Input form	Essential for data input
>	Level 1 header	Aim to have one H1 on each page, containing a description of what the page is about.
>	Level 2 header	Defines a section of the page
>	Level 3 header	Defines a sub-section of the page (should always follow an H2 in the logical hierarchy)
>	Level 4 header	Etc. Less commonly used
>	Level 5 header	Less commonly used. Only complex academic documents will break down to this level of detail.
>	Level 6 header	Less commonly used
>	Document head	Essential. Contains information about a page that does not constitute content to be communicated as part of the page.
>	Horizontal rule	Display info with no semantic value – never use it. “Horizontal”, by definition, is a visual attribute.
>		Core element of every web page.
>	Show an image	Vital. Always use the alt or longdesc attributes when the image has content value
>	Input fields within forms	Vital. (I prefer to use for buttons and submit buttons though)
>	Old type of search input	Not really used any more. Use instead.
>	Italicised text	Display info – never use it
>	Keyboard input	Display info – never use it
>	Defines a relationship to another document	Commonly used to reference external stylesheets, but has other minor uses
>	List item	Specifies an item in an unordered or ordered list ( or )
	Client-side imagemap	May have occasional value, but only use when absolutely necessary
>	Makes text scroll across the screen	See
>	Menu item list	Deprecated. Do not use. Use other standard list types instead.
>	Meta-information	Useful way to insert relevant information into the section of the page that does not need to be displayed.
>	Ordered list	Type of list where the order of elements has some meaning. Generally rendered with item numbers (best managed with CSS).
>	Selection list option	Vital for options within a drop-down control.
>	Parameter for Java applet	Used in conjunction with an or tag to pass additional setting information at runtime.
>	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.)
>	Paragraph	Only use to denote a paragraph of text. Never use for spacing alone.
>	Short quotation	Use for inline quotations (whereas should be used for quotations of a paragraph or more). Often used in conjunction with to cite the quotation’s source.
>	Denotes sample output text	Similar to the tag. Rarely used. Avoid.