HTML basics · Lesson 12 of 12 · 10 minutes

HTML basics: Reusable class names

Classes let multiple elements share presentation. IDs should identify a single element within a document.

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Your objectives

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1
Build reusable class names
Build this first target: (class="notice") containing “Workshop starts soon.”. Inspect the structure before checking the lesson.
Hint & worked example
Classes let multiple elements share presentation. IDs should identify a single element within a document.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
Workshop starts soon.
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.
2
Extend the reusable class names example
Extend your file to include: (class="notice") containing “Workshop starts soon.”; (class="notice") containing “Bring a notebook.”. Inspect the structure before checking the lesson.
Hint & worked example
Classes let multiple elements share presentation. IDs should identify a single element within a document.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
Workshop starts soon.
Bring a notebook.
```
Common mistake to avoid: Replacing semantic elements with generic divs automatically improves accessibility.
3
Verify the complete reusable class names pattern
Finish the pattern with: (class="notice") containing “Workshop starts soon.”; (class="notice") containing “Bring a notebook.”; (class="notice urgent") containing “Doors close at ten.”. Inspect the structure before checking the lesson.
Hint & worked example
Classes let multiple elements share presentation. IDs should identify a single element within a document.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
Workshop starts soon.
Bring a notebook.
Doors close at ten.
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.

Understand the pattern

Classes let multiple elements share presentation. IDs should identify a single element within a document.

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

<p class="notice">Workshop starts soon.</p>
<p class="notice">Bring a notebook.</p>
<p class="notice urgent">Doors close at ten.</p>

Classes let multiple elements share presentation. IDs should identify a single element within a document.

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 reusable class names?A visual appearance alone guarantees the intended HTML meaning.Replacing semantic elements with generic divs automatically improves accessibility.Classes let multiple elements share presentation. IDs should identify a single element within a document.

Apply it elsewhere

You reuse reusable class names 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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