The term goniometry is derived from two Greek words, gonia, meaning "angle" and metron, meaning "measurement". A goniometer is an instrument that measures the available range of motion at a joint. Goniometry is the art and science of measuring the joint ranges in each plane of the joint. If a patient or client suffers from a decreased range of motion in a particular joint, at the initial evaluation, the therapist can use a goniometer to evaluate what the range of motion is, and then ensure that the intervention works in subsequent sessions by using the goniometer. There are different types of goniometers; the most used is the standard universal goniometer, which is either made from plastic or metal tools. It consists of a stationary arm, a moving arm, and a fulcrum. The telescopic-armed goniometer, Gravity Dependent Goniometer, fluid goniometer, pendulum, electronic goniometer, and some AI-based Application smartphones are other types of goniometer used for joint ra...