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HTML

HTML Classes

HTML classes assign reusable identifiers to elements.

Read Time

5 min read

Difficulty

Beginner

Last Updated

Jun 15, 2026

Version

v1.0.0

Introduction

HTML uses the `class` attribute to group elements. Multiple elements can share the exact same class name. CSS and JavaScript target these classes to apply styles or behavior.

Syntax

1<!-- class syntax -->
2<p class="intro highlight">Text</p>

Example

1<!-- this applies classes -->
2<!DOCTYPE html>
3<html lang="en">
4  <head>
5    <meta charset="UTF-8">
6    <meta name="viewport" content="width=device-width, initial-scale=1.0">
7    <title>Classes</title>
8  </head>
9  <body>
10    <p class="error">Something went wrong.</p>
11  </body>
12</html>

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Key Points

The `class` attribute groups elements.
Multiple elements share the same class.
One element accepts multiple classes.
CSS targets classes to style pages.

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