A fingerprint recognition feature from Apple. On a Mac computer or Magic Keyboard with Touch ID, you can use it to unlock your Mac and some password-protected items, switch quickly between users, use Apple Pay to make purchases on the web, and purchase items from the iTunes Store, the App Store, and Apple Books.
Note: Touch ID on Magic Keyboard (available on some models) is only compatible with Mac computers with Apple silicon.
To set up Touch ID, choose Apple menu > System Preferences, then click Touch ID. To use Touch ID, place your finger on it.