Semantic structure · Lesson 1 of 10 · 7 minutes

Semantic structure: Site header

A top-level header introduces the page or site. It is not a replacement for the main content landmark.

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Your objectives

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1
Build site header
Build this first target: <header>. Inspect the structure before checking the lesson.
Hint & worked example
A top-level header introduces the page or site. It is not a replacement for the main content landmark.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<header></header>
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.
2
Extend the site header example
Extend your file to include: <header>; <p> inside <header> containing “Community library”. Inspect the structure before checking the lesson.
Hint & worked example
A top-level header introduces the page or site. It is not a replacement for the main content landmark.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<header><p>Community library</p></header>
```
Common mistake to avoid: Replacing semantic elements with generic divs automatically improves accessibility.
3
Verify the complete site header pattern
Finish the pattern with: <header>; <p> inside <header> containing “Community library”; <nav> inside <header> (aria-label="Primary"); <a> inside <nav> (href="/web/") containing “Learn”. Inspect the structure before checking the lesson.
Hint & worked example
A top-level header introduces the page or site. It is not a replacement for the main content landmark.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<header><p>Community library</p><nav aria-label="Primary"><a href="/web/">Learn</a></nav></header>
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.

Understand the pattern

A top-level header introduces the page or site. It is not a replacement for the main content landmark.

Misconceptions to reject

A visual appearance alone guarantees the intended HTML meaning.
Replacing semantic elements with generic divs automatically improves accessibility.

The preview is a sanitized subset, not a full browser compatibility test.

Worked example and expected result

<header><p>Community library</p><nav aria-label="Primary"><a href="/web/">Learn</a></nav></header>

A top-level header introduces the page or site. It is not a replacement for the main content landmark.

Try a variation

Adapt the final example to a different project name while retaining its structure and relationships. A different context still needs a real browser and accessibility check.

Explain it

Which statement correctly explains site header?Replacing semantic elements with generic divs automatically improves accessibility.A top-level header introduces the page or site. It is not a replacement for the main content landmark.A visual appearance alone guarantees the intended HTML meaning.

Apply it elsewhere

You reuse site header in a different project. What must still be verified?The meaning, relationships, and accessible names in the new document.Nothing; passing a single exercise guarantees every future use.Only whether the source code has the same number of lines.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

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MDN: HTML structure