Semantic structure · Lesson 6 of 10 · 7 minutes

Semantic structure: Supporting asides

An aside contains related but secondary material. Essential task instructions belong in the main flow.

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Your objectives

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1
Build supporting asides
Build this first target: <main>; <h1> inside <main> containing “Practice session”; <p> inside <main> containing “Read the supplied log.”. Inspect the structure before checking the lesson.
Hint & worked example
An aside contains related but secondary material. Essential task instructions belong in the main flow.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<main><h1>Practice session</h1><p>Read the supplied log.</p></main>
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.
2
Extend the supporting asides example
Extend your file to include: <main>; <h1> inside <main> containing “Practice session”; <p> inside <main> containing “Read the supplied log.”; <aside> (aria-labelledby="tip"); <h2> inside <aside> (id="tip") containing “Background reading”. Inspect the structure before checking the lesson.
Hint & worked example
An aside contains related but secondary material. Essential task instructions belong in the main flow.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<main><h1>Practice session</h1><p>Read the supplied log.</p></main>
<aside aria-labelledby="tip"><h2 id="tip">Background reading</h2></aside>
```
Common mistake to avoid: Replacing semantic elements with generic divs automatically improves accessibility.
3
Verify the complete supporting asides pattern
Finish the pattern with: <main>; <h1> inside <main> containing “Practice session”; <p> inside <main> containing “Read the supplied log.”; <aside> (aria-labelledby="tip"); <h2> inside <aside> (id="tip") containing “Background reading”; <a> inside <aside> (href="/unix/") containing “UNIX fundamentals”. Inspect the structure before checking the lesson.
Hint & worked example
An aside contains related but secondary material. Essential task instructions belong in the main flow.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<main><h1>Practice session</h1><p>Read the supplied log.</p></main>
<aside aria-labelledby="tip"><h2 id="tip">Background reading</h2><a href="/unix/">UNIX fundamentals</a></aside>
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.

Understand the pattern

An aside contains related but secondary material. Essential task instructions belong in the main flow.

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

<main><h1>Practice session</h1><p>Read the supplied log.</p></main>
<aside aria-labelledby="tip"><h2 id="tip">Background reading</h2><a href="/unix/">UNIX fundamentals</a></aside>

An aside contains related but secondary material. Essential task instructions belong in the main flow.

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 supporting asides?A visual appearance alone guarantees the intended HTML meaning.Replacing semantic elements with generic divs automatically improves accessibility.An aside contains related but secondary material. Essential task instructions belong in the main flow.

Apply it elsewhere

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

Keep the momentum.

Complete the lab, then explain and apply the pattern.

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MDN: HTML structure