Detailed answer
Start sets an ordered list's initial number.
An individual li can supply a value when a specific item must restart numbering. Keep the sequence understandable when copied or read aloud. Use real numbering semantics rather than typing a number into each item and manually maintaining the sequence.
Example
<ol start="4"><li>Open the HTML file.</li><li>Check the preview.</li><li>Fix errors.</li></ol>
Understanding the behavior
An ordered list's start attribute sets its starting ordinal, while an individual li can set a value. These are useful when a sequence continues after explanatory content. Styling alone should not communicate numbering that differs from the real list order.
Practical implementation notes
Check the sequence after inserting or removing an item. Hard-coded numbers inside the text can drift out of sync with actual numbering and produce confusing duplicate numbers for assistive technology.
How to check it
Set start on the next ordered list and inspect the displayed numbering.
Expected result
The continuation begins at 4 without manually typing numbers into item text.
Watch out: Use ol only when the order conveys useful meaning.
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