Three measures of the same contracts at three timings: contract value at signature, invoices issued, and value recognised as earned. They differ by deferral and release, and a bridge between them is published with the numbers. Every report names which of the three it shows.
Bookings equal the sum of billings equal the sum of revenue. A contract that fails this has a schedule that was never built.
"Revenue" on a slide that shows bookings is the failure the rule exists to prevent.
Three totals for the same contracts: value signed in the period, invoices issued in the period, and revenue recognised in the period. A bridge shows the timing differences between each pair.
A three-year contract for $360,000 signed in March, billed annually in advance, is $360,000 of bookings, $120,000 of billings and $100,000 of revenue in the first fiscal year.
Sales reports bookings, finance reports revenue, and the board sees both called sales. Each is right and they will never match without the bridge.