Cartesian and polar coordinates are two distinct ways of describing the position of points in a plane. In Cartesian coordinates, a point is represented by an ordered pair (x, y), which tells you how far to move horizontally and vertically from the origin. This system is ideal for graphing straight lines and algebraic equations. On the other hand, polar coordinates use a radius r and an angle θ to locate a point, where r is the distance from the origin and θ is the angle from the positive x-axis.