The rectangular coordinate system, also known as the Cartesian coordinate system, was developed by the French mathematician René Descartes. It uses two perpendicular number lines, the x-axis and y-axis, that intersect at the origin (0,0) to locate points in a plane. Each point is identified with an ordered pair of numbers known as Cartesian coordinates that represent the distance from the origin on the x-axis and y-axis. The system divides the plane into four quadrants and allows points to be easily plotted and located.