A fingerprint recognition feature available on some Mac computers. With Touch ID, you can 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 iBooks Store.
To use Touch ID, place your finger on Touch ID at the right end of the Touch Bar.
To set up Touch ID, choose Apple menu > System Preferences, then click Touch ID.
For more information about Touch ID, see the Apple Support article Use Touch ID on MacBook Pro.