Parametric Equation

A parametric equation expresses several quantities, such as the coordinates of a point, as functions of one or more variables called parameters. With a single parameter, parametric equations commonly describe the trajectory of a moving point, tracing out a parametric curve, while two parameters describe a parametric surface. For example, x equal to cosine t and y equal to sine t together trace the unit circle as t varies, and such parameterizations are not unique, since the same curve or surface can be expressed by more than one parametric representation. Parametric equations extend beyond curves and surfaces to describe manifolds and algebraic varieties of higher dimension, and are widely used in kinematics to represent an object moving along a trajectory as a function of time. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/