Global Attributes: id, class, style, and title

Global attributes can be used on almost any HTML element, regardless of its type. Four of the most common ones:

id — a unique identifier for one specific element on the page. No two elements should share the same id.

<div id="main-header">...</div>

class — a reusable label that can be applied to many elements, primarily used to attach shared CSS styles or JavaScript behavior.

<p class="highlight">Important note</p>
<p class="highlight">Another important note</p>

style — applies inline CSS directly to one element. Useful for quick tests, but generally discouraged in real projects since it mixes structure and presentation.

<p style="color: red; font-weight: bold;">Warning text</p>

title — adds a tooltip that appears when the user hovers over the element.

<abbr title="HyperText Markup Language">HTML</abbr>

A practical rule: use id when you mean exactly one element, class when you mean a group of elements that share behavior or style, and reach for style only when nothing else is more appropriate — a linked stylesheet is almost always the better long-term choice.