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 See what your friends are listening to.
Special playlists (like Replay): See the Apple Support article > 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 Adjust the sound in Music on iPad