A normal-tangential coordinate frame is a mathematical tool used to describe an object's position and movement in space. This frame is essential in mechanics and dynamics when analyzing motion or forces acting on an object. The normal-tangential coordinate frame can also be referred to as the radial-tangential coordinate frame or radial-normal coordinate frame. In some contexts, it may also be called the polar coordinate frame or orthogonal coordinate frame. Regardless of its name, the normal-tangential coordinate frame is a valuable tool used by scientists and engineers to understand the movement of objects in space.