# map and filter

map turns every item of an array into something new, filter keeps only the items that pass a test, and chained together they turn raw data into exactly the list a screen needs.

![Cheat sheet: map and filter](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/10/829bf97b38b84c1db460718c4ea70752.webp)

- Category: JavaScript
- Level: Apprentice
- Tags: Array Iterator Method, filter() (javascript), JavaScript, map() (javascript), Method Chaining (javascript)
- Updated: November 1, 2026

Source: https://www.ask-codey.com/cheat-sheets/javascript-array-methods-map-and-filter-cheat-sheet