The three-dimensional coordinate system is an extension of the twodimensional coordinate system invented in 1637 by French mathematician René Descartes (1596–1650). Soon after Descartes wrote about his twodimensional coordinate system, other mathematicians took Descartes's idea and expanded it from a two-dimensional plane to three-dimensional space. This new development greatly enlarged the uses of the coordinate system.

With the enhancement of the two-dimensional coordinate system to three dimensions, it was possible to locate any object in three-dimensional space. For example, with Descartes's two-dimensional coordinate system, you could describe the location of a coin on the floor of a room by referring to how many feet the coin was located from a front wall and a side wall. However, in a two-dimensional coordinate system, it is impossible to describe the location of an object that is off the plane of the floor, such as the location of a...