If you arrange your car loan using the Personal Contract Purchase (PCP) method, you defer a percentage of the total cost of the car to the end of the contract.
This percentage is known as the Minimum Guaranteed Future Value (MGFV).
The MGFV, plus your deposit, is subtracted from the selling price of the vehicle and your monthly payments are based on the balance (plus interest on the balance and the MGFV).
At the end of the agreement you can opt to make a balloon payment to keep the car based on the MGFV.