Semantic HTML Layout
Use meaningful landmarks instead of generic divs everywhere.
What this solves
Structure a tool page with header, nav, main, sections and footer. This pattern is useful when the business question is clear but a generic tutorial is too abstract.
The rule
Choose elements by meaning, not by default appearance.
<header>...</header>
<main><section>...</section></main>
<footer>...</footer>Real-work checklist
- Define the business key and expected grain before writing the formula, query or markup.
- Test the pattern on a small known sample where you can verify the answer manually.
- Check missing values, duplicates and data types before trusting a large result.
- Scale to the real file or database only after the logic is proven.
Common mistake
Do not use section or article only because you need a styling hook.