The days of OS X—whether you pronounced it “10” or “X”—are over. Apple’s operating system now goes by macOS, in keeping with its cousins on the iPad and iPhone (iOS), on the Apple TV (tvOS), and on the Apple Watch (watchOS). macOS 10.12 Sierra improves upon and adds to the big changes OS X 10.11 El Capitan brought us. You’ll find updates—some substantial, some subtle—to key apps as well as new integration of the macOS and the iOS experiences. Use the links in this chapter to jump straight to the new feature you’re most interested in.