HTML attribute

Description

Common attributes

• The id attribute provides a document-wide unique identifier for an element. This can be used as CSS selector to provide presentational properties, by browsers to focus attention on the specific element, or by scripts to alter the contents or presentation of an element. Appended to the URL of the page, the URL directly targets the specific element within the document, typically a sub-section of the page. For example, the ID "Attributes" in http://en.wikipedia.org/wiki/HTML#Attributes.
• The class attribute provides a way of classifying similar elements. This can be used for semantic purposes, or for presentation purposes. Semantically, for example, classes are used in microformats. Presentationally, for example, an HTML document might use the designation class="notation" to indicate that all elements with this class value are subordinate to the main text of the document. Such elements might be gathered together and presented as footnotes on a page instead of appearing in the place where they occur in the HTML source. Another presentation use would be as a CSS selector.
• An author may use the style non-attributal codes presentational properties to a particular element.The style attribute can be used on any HTML element. It is considered better practice to use an element's id or class attributes to select the element with a stylesheet, though sometimes this can be too cumbersome for a simple and specific or ad hoc application of styled properties.
• The title attribute is used to attach subtextual explanation to an element. In most browsers this attribute is displayed as what is often referred to as a tooltip.

  Varieties

• Usually the required and optional attributes modify specific HTML elements
• While the standard attributes can be applied to most HTML elements.
• Event attributes, added in HTML version 4, allow an element to specify scripts to be run under specific circumstances.

  Required and optional

Used by one element

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  Used by two elements

• and :
• * coords — coordinates of an or a within it.
• * shape — shape of an or a within it. Values: default, rect, circle, poly.
• and :
• * hreflang — Language code of the linked document.
• * rel — Nature of the linked document. Free text for, but uses a set of terms.
• * rev — Nature of the currently displayed page. Varies for and as for rel.
• and :
• * archive — archive URL
• * codebase — base URL
• and :
• * color — text color '
• * face — font family '
• and :
• * span — number of columns spanned
• and :
• * datetime — date and time of text or.
• and :
• * accept — types of files accepted when uploading or
• and :
• * frameborder — value specifies whether to display a border around the or.
• * marginheight — top and bottom margins in pixels around the or.
• * scrolling — value specifies whether to display scroll bars around the or.
• * marginwidth — left and right margins in pixels around the or.
• and :
• * cols — number of visible columns in or '
• * rows — number of visible rows in or '
• and :
• * usemap — specifies name of a map element to use with -or- URL of an image-map to use with.
• and :
• * readonly — specifies read-only text for and.
• and :
• * media — specifies display device for and. Values: all, aural, braille, handheld, print, projection, screen, tty, TV.
• and :
• * label — description text for an or.
• and :
• * abbr — abbreviated version of a table or.
• * axis — category name for a table or.
• * colspan — number of columns spanned by a table or.
• * nowrap — prevents wrapping of a table or.
• * rowspan — number of rows spanned by a table or.
• * scope — no effect on normal browser display, but marks a table or as a logical header for other cells. Values: col, colgroup, row, rowgroup.

  Used by multiple elements

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• alt —,,,
• bgcolor —,,,,
• border —,,
• char —,,,,,,,
• charoff —,,,,,,,
• charset —,,
• cite —,,,
• compact —,,,
• disabled —,,,,,
• height —,,, . Also deprecated in,
• href —,,,
• hspace —,. Also deprecated in
• longdesc —,,
• name —,,,,,,,,,,,,
• size —,,,,
• src —,,,,
• target —,,,,
• type —,,,,,,,,,
• valign —,,,,,,,
• value —,,,,
• vspace —,,
• width —,,,,,,,,,,

  Standard attributes

Event attributes