The screwdriver is familiar to almost everyone. It's basic job it to allow us to turn a fastener. Common types of screwdriver are slotted (or flat-blade), Phillips (cross-slotted), and Torx. The Land Rover uses all three varieties, but the Torx is really a special application and you probably won't encounter it in most repairs.
There are several sizes of slotted and cross slotted screws and therefore you should use the proper size screwdriver to fit it. Rounding off a screw is a very frustrating experience and can usually be avoided by using the proper tool. It is important to choose a screwdriver with good steel so that the tip doesn't deform, and one with a comfortable handle as they can be rather hard to grip. The larger the grip, the more torque you can apply to the fastener with the same effort.