Bookings is the total value of new contracts that go into effect in a period.
Bookings is differs from new ARR because it also includes the value of renewal deals. It's important to track bookings to understand the total value of new contracts that is locked in for at least another year. Sales teams often work on new, expansion, and renewal deals, so total bookings help to show their total contribution to the company. Bookings can be tracked on an ARR or TCV basis.