Detailed answer
Datalist offers suggestions to a compatible input without forcing selection from them.
Match the input list attribute to the datalist id. Use select when the person must choose a fixed option. Browser and assistive-technology behavior varies, so test the combinations your users need rather than assuming identical presentation.
Example
<label for="topic">HTML topic</label><input id="topic" name="topic" list="topics"><datalist id="topics"><option value="Forms"><option value="Tables"></datalist>
Understanding the behavior
Datalist provides suggestions to a compatible input while still allowing other values. It differs from a select, which presents a constrained option set. Browser and assistive-technology experiences vary, so test the actual audience's supported combinations.
Practical implementation notes
If the server only accepts certain values, validate that requirement separately. Do not assume that selecting from suggestions is mandatory or that every browser presents the same dropdown interface.
How to check it
Associate list with the datalist id and enter a value not among the suggestions.
Expected result
The input can accept free text; a fixed-choice rule needs separate validation.
Watch out: Suggestions are not server-side validation of allowed values.
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