A right angle screwdriver is a device for driving screws into surfaces; it has a handle that is held parallel to the surface into which the screw is inserted. Traditional screwdrivers tend to consist of one straight part with the handle parallel to the head of the screwdriver, and both are held perpendicular to the surface into which the screw is inserted. In some cases, there is insufficient space above the intended surface for a traditional screwdriver to be used. In such cases, one can use a right angle screwdriver, as such devices require much less clearance above the surface of interest. Some screwdrivers are built with adjustable heads, meaning that the screwdrivers can be used in the traditional vertical arrangement or as a right angle screwdriver.
The main advantage of a right angle screwdriver is that it can be used in circumstances wherein a traditional screwdriver cannot. If one needs to drive a screw into a surface that has only a few inches (about 7 or 8 cm) of clearance, a traditional screwdriver cannot be used effectively. A right angle screwdriver, on the other hand, may take up an inch (about 2.5 centimeters) or less above the surface of interest. The handle projects outward, not upward like a traditional screwdriver.
While a right angle screwdriver can be used to drive screws into hard-to-reach spaces, it may not be as easy to use as a traditional screwdriver. With a traditional screwdriver, one inserts or removes the screw by turning the entire handle, which is directly in line with the screw. Turning a right angle screwdriver like this would involve turning the handle in a wide circle around the screw. Space constraints and difficulty physically carrying out this motion may require one to turn the screw a little bit, remove the head of the screwdriver from the screw, move the screwdriver back to its starting position, turn the screw a little farther, remove, and repeat. This is not nearly as efficient as using a traditional screwdriver, but space constraints may make it necessary.
There are a few different types of right angle screwdrivers. Some have only one size head that is firmly attached to the handle. While these are generally the least expensive, they also fit only a small range of screws. Others allow the user to switch out a variety of different screwdriver heads of different shapes and sizes — these tend to be useful because of their versatility. Still others allow one to adjust the angle in order to fit a variety of restricted spaces.