Class and Id Attributes

Here is the explanation of Class and Id Attributes:

• In HTML, the class and id attributes are used to assign specific identifiers or styles to elements.
• These attributes help in styling elements with CSS, selecting elements using JavaScript, and providing a way to reference or target specific elements within an HTML document.

class Attribute:

The class attribute is used to assign one or more class names to an HTML element. A class is a way to group multiple elements together and apply the same styles or behaviors to all of them.

Syntax:

Example:

In CSS, you can style elements with a particular class using the dot notation (.):

CSS:

id Attribute:

The id attribute is used to assign a unique identifier to a specific HTML element within a document. Unlike classes, which can be shared among multiple elements, an id must be unique within the entire HTML document.

Syntax:

Example:

In CSS, you can style elements with a particular ID using the hash notation (#):

CSS:

When to Use class vs. id:

• Class:
  • Use when multiple elements share the same styles or behavior.
  • Multiple elements can have the same class.
  • Class names are reusable.
• ID:
  • Use when an element requires a unique identifier.
  • IDs are used for specific, one-of-a-kind elements.
  • An element should have only one ID.

Usage in JavaScript:

Both class and id attributes are commonly used in JavaScript for selecting and manipulating elements.

Using class in JavaScript:

Using id in JavaScript: