In HTML, headers usually refer to heading elements that define titles or section headings in a webpage.

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1. HTML Heading Tags

HTML provides six levels of headings:

<h1>Heading Level 1</h1>
<h2>Heading Level 2</h2>
<h3>Heading Level 3</h3>
<h4>Heading Level 4</h4>
<h5>Heading Level 5</h5>
<h6>Heading Level 6</h6>

Meaning:

• <h1> → Main page title (most important)
• <h2> → Section headings
• <h3> → Subsection headings
• <h4> → Smaller subheadings
• <h5> and <h6> → Least important headings

Example Structure:

<h1>My Website</h1>
<h2>About Us</h2>
<p>We are a tech company...</p>
<h2>Services</h2>
<h3>Web Development</h3>
<p>We build websites...</p>

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2. SEO & Accessibility Notes

• Search engines use headings to understand content hierarchy.
• Use only one <h1> per page for the main title.
• Don’t skip heading levels for style reasons (e.g., jump from <h1> to <h4> without logical order).
• Screen readers rely on heading structure for navigation.

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3. Styling Headings

Headings have default sizes, but you can change them with CSS:

<h2 style="color: blue; font-size: 30px;">Custom Heading</h2>

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4. Not to Confuse with <header> Tag

• <header> is a semantic section element in HTML5 used to group introductory content or navigation.
• It can contain <h1>–<h6>, logos, menus, etc.
  Example:

<header>
  <h1>My Blog</h1>
  <nav>
    <a href="#">Home</a> | <a href="#">About</a>
  </nav>
</header>

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