Introduction
When learning HTML and CSS, beginners often get confused between ID vs Class. Both are used to target and style HTML elements, but they serve different purposes. In this blog, we will explain the difference between ID and Class in HTML, their use cases, and how they impact web development.
What is an ID in HTML?
An ID is a unique identifier for an element in HTML. It is defined using the id attribute and can only be used once per page.
- Syntax:
<div id="header"></div> - IDs are unique and must not be repeated.
- They are often used for JavaScript functions or unique styling.
Example:
<h1 id="main-title">Welcome to My Website</h1>Here, main-title is unique and can only be used for this single heading.
What is a Class in HTML?
A Class is used to style multiple elements with the same CSS properties. Unlike ID, you can use a class multiple times on a page.
- Syntax:
<div class="content"></div> - Classes can be reused across multiple elements.
- Ideal for group styling.
Example:
<p class="text">This is a paragraph.</p>
<p class="text">This is another paragraph.</p>Both paragraphs share the same styling using the text class.
Key Difference Between ID vs Class in HTML
| Feature | ID | Class |
|---|---|---|
| Uniqueness | Must be unique per page | Can be used multiple times |
| Selector in CSS | #idname {} | .classname {} |
| Use case | Unique element (header, footer, main title) | Reusable elements (buttons, text styles) |
| Priority in CSS | Higher priority | Lower priority compared to ID |
| JavaScript | Used to directly select one element | Used to select multiple elements |
Best Practices for Using ID and Class
- Use ID for unique elements like
header,footer, ormain-title. - Use Class for repeated styling such as
button,card, ortext. - Avoid using IDs for styling unless necessary. Instead, rely on classes for cleaner, reusable CSS.
Conclusion
The difference between ID and Class in HTML is simple: ID is unique, Class is reusable. Understanding this concept is crucial for writing clean, maintainable, and SEO-friendly code.
If you’re building websites, always remember: ID for one, Class for many.
