Intro to playlists in Music on iPhone
A playlist is a custom compilation of songs and music videos. You might want to create a playlist to do the following:
Suit a specific mood or occasion. For example, you could create a playlist for a dinner party, a wedding, or your morning workout.
Select certain songs to share with others on your local network or to sync with your Mac or Windows device.
Organize your music library.
When you subscribe to Apple Music, there are a few other types of playlists available:
Favorite Songs playlist: See Mark items as favorites.
Playlists created by any Apple Music contributor: See Add music to iPhone and listen offline.
Playlists created by other subscribers that you follow: See See what your friends are listening to.
Special playlists (like Replay): See the Apple Support article How to get your Apple Music Replay.
Collaborative playlists: See Collaborate on a playlist and Join a collaborative playlist.
Changes you make to your music library (creating playlists, for example) are updated across all your devices when Sync Library is turned on (go to Settings > Apps > Music, then turn on Sync Library). If you’re not an Apple Music subscriber, the changes appear in your library the next time you sync with your computer.