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What is the difference between map and forEach?

Q: What is the difference between map and forEach?

**Core concept (TL;DR).** Both loop over every element, but map **returns a new array** of the callback's return values (a transformation), while forEach returns undefined and exists purely for **side effects**. Use map when you want a result; use forEach when you just want to *do* something each iteration. map builds a new array · forEach returns undefined <text x="135" y="62" fill="#22c55e" font-size="11" font-weight="700" text-

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