Touch Bar was installed from MacBook Pro (Late 2016). With the Touch Bar, you can use fingerprint authentication (Touch ID) for unlocking the Mac lock screen, Apple Pay, iTunes, and the Apple Store.
How to set (on/off) Touch ID on a Mac with Touch Bar
Add/remove Touch ID fingerprints
With Touch ID, you can unlock your Mac with your fingerprint and shop with Apple Pay, iTunes and the App Store. please put your finger Repeat the process of placing and releasing your finger on Touch ID. Repeat the process of placing and releasing your finger on Touch ID.
Delete Fingerprint
See here for how to use and set up the Touch Bar/Touch ID.
How to use and set up Touch Bar/Touch ID
