JavaScript Arrays

Arrays with Real API Data

Production apps rarely loop over fruit lists. You work with API payloads — like Spotify playlist tracks returned from the Web API.

• map — transform each track into UI-ready data
• filter — narrow results (e.g. songs over 3 minutes)
• reduce — aggregate totals (playlist duration, popularity scores)

const res = await fetch(
  "https://api.spotify.com/v1/playlists/37i9dQZEVXbMDoHDONVNfs/tracks?limit=5"
);
const { items } = await res.json();
const names = items.map((item) => item.track.name);
console.log(names);

// Click Run — watch API traces and console output