HTML Id

The HTML id attribute is used to specify a unique id for an HTML element.

Using The id Attribute

You cannot have more than one element with the same id in an HTML document. The `id` attribute is often used to point to a specific style declaration in a style sheet. It is also used by a JavaScript to access and manipulate the element with the specific id.

The syntax for id is: write a hash character (#), followed by an id name. Then, define the CSS properties within curly braces {}.

ID Attribute Example

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The id name is case sensitive! The id name must contain at least one character, and must not contain whitespaces (spaces, tabs, etc.).

Difference Between Class and ID

A class name can be used by multiple HTML elements, while an id name must only be used by one HTML element within the page:

Class vs ID Example

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