A contract is the collective term for the information entered for a given crew member.
Such information includes:
The start, end/anniversary date of a crew member
Whether or not a trial period was included at the start
How much leave the crew member is entitled too within the contractual period, and how it is accrued.
Flight allowance granted to the crew member under the terms of their contract
The information specified in this contract is used to calculate ongoing and future leave balances for your crew as well as providing ongoing support for your leave management process.