• An HTML attribute is a modifier of an HTML element.
• HTML attributes generally appear as name-value pairs, separated by "=", and are written within the start tag of an element, after the element's name.
• Where tag names the HTML element, attribute is the name of the attribute, set to the provided value.
• The value may be enclosed in single or double quotes, although values consisting of certain characters can be left unquoted in HTML (but not XHTML).
• Leaving attribute values unquoted is considered unsafe.

• Attributes must be in lower case.
• Attribute value must be in double qoutes("").
• Attributes is just like key-value pair and written as attribute="value"



<tag attribute="value">(content to be modified by the tag)</tag>



• Common attributes are :
1. id : Defines a unique id for an element.
2. class : Refers to a class in style sheet( css).
3. style : Defines a specific inline style sheet ( css).
4. title : Defines more information about element.

Example

< element id="Id" class="Class" style="color:red;" title="Techknow Heights">

• Event occur when user come and click on button, or over mouse on any link.
• Thus you must be create your event handler in java script or vb script.
• HTML5 give us many event attribute to handle all that event and less code of java script.
• In HTML5 you can call any other java script function from event attribute.

HTML5 has several new attributes for <form> and <input>.

New attributes for <form>:

• autocomplete
• novalidate

New attributes for <input>:

• autocomplete
• autofocus
• form
• formaction
• formenctype
• formmethod
• formnovalidate
• formtarget
• height and width
• list
• min and max
• multiple
• pattern (regexp)
• placeholder
• required
• step