HTML Attributes

Attributes are extra information attached to an element. They live inside the opening tag and follow name="value".

Anatomy of an attribute

<a href="https://example.com" target="_blank">Visit</a>

Every attribute has a name and a value. The value is usually wrapped in double quotes.

Common attributes

• href — link destination on <a>
• src — image or script source
• alt — descriptive text for images
• class — a CSS hook (many elements can share it)
• id — a unique identifier

<img src="cat.png" alt="A cat sleeping" class="photo" id="hero-cat" />

Boolean attributes

Some attributes have no value — their presence alone is the value.

<input type="text" disabled />
<button disabled>Not clickable</button>
<input type="checkbox" checked />

• disabled — element is not interactive
• checked — checkbox starts selected
• required — field must be filled

data-* attributes

Any attribute prefixed with data- is available to JavaScript and never affects rendering.

<button data-tooltip="Save your work">Save</button>