Park

(p rk) (v.) To lock the read/write head of a hard disk drive in a safe position so that the disk will not be damaged while moving the drive. The space where the head is parked typically is called the landing zone. Parking the disk is particularly important for portable computers, which are moved frequently. The disk will automatically unpark itself once you turn the power on.

All modern disk drives support automatic head parking, in which the drive automatically parks the head whenever the power is turned off.