The word goniometer is derived from the Greek terms gonia and metron, which mean angle and measure, respectively. A goniometer is an instrument that measures an angle or allows an object to be rotated to a precise angular position, and is used in motion control applications. Goniometers are similar to linear stages, but rather than providing linear movement, the stage partially rotates about a fixed point above the mounting surface of the stage. They also allow tip and tilt adjustment of any optical component and are often used to accurately direct lasers and align mirrors in beam steering applications.