Touch Bar
A feature at the top of the keyboard on some Mac computers. The Touch Bar lets you use familiar gestures—like tap, swipe, or slide—to adjust settings, use Siri, access function keys, and do tasks in apps.
The Touch Bar includes Touch ID, which lets you unlock your Mac and some password-protected items, use Apple Pay to make purchases on the web, and purchase items from the iTunes Store, App Store, and Apple Books.
By default, the Touch Bar shows the Control Strip, which lets you adjust common settings—like brightness and volume—and ask Siri. You can expand the Control Strip to access additional settings and features, such as Mission Control and Launchpad, and even customize it.
The other buttons in the Touch Bar vary, depending on the app you’re using or the task you’re performing. Here’s how the Touch Bar looks when you tap in the Touch Bar to run code in Swift Playgrounds.
See the Apple Support article How to use the Touch Bar on your MacBook Pro.