A PLAYLIST IS A GROUP OF SONGS YOU GATHER FROM YOUR ITUNES library that you think go well together. You can include pretty much any set of tunes arranged in any order. For example, if you’re having a party, you can make playlists out of the dance music in your iTunes library. If you’re in a 1960s Brit-girl pop mood, you can whip together the hits of Dusty Springfield, Lulu, and Petula Clark. Some people may question your taste if you, say, mix tracks from La Bohéme with Queen’s A Night at the Opera, but hey—it’s your playlist.

Creating playlists has become something of an art form since the iPod arrived in 2001. You can find books filled with sample playlists. Academics around the world write papers about group dynamics and cultural identity after studying how people create playlists—and which ones they choose to share with others. You can publish your own playlists in the iTunes Store (see Publish Your Own Playlists) so others can bear witness to your mixing prowess. Some nightclubs even invite people to hook up their iPods so they can share their playlists with the dance-floor audience.