Geo 1995 Prizm Owner's Manual page 53

Door Locks
There are several ways to lock and unlock your vehicle:
From the outside, use your key. To lock the door, turn
the top of the key toward the front of the car. If you have
power door locks, all the doors will lock.
Insert the key in any front door and turn the top of
the key toward the rear of the car to unlock the door.
If your vehicle has power door locks, turn the key once
to unlock the driver's door only. Turn the key back
to center, then toward the rear again to unlock all the
doors. Using the key in the passenger's door will unlock
all the doors.
2-3