Cartesian coordinate system | rectangular coordinates

Cartesian coordinates are the usual coordinate system, originally described by Descartes, in which points are specified as distances to a set of perpendicular axes. Also called rectangular coordinates.

Cartesian coordinates are rectilinear two- or three-dimensional coordinates (and therefore a special case of curvilinear coordinates) which are also called rectangular coordinates. The two axes of two-dimensional Cartesian coordinates, conventionally denoted the x- and y-axes (a notation due to Descartes), are chosen to be linear and mutually perpendicular. Typically, the x-axis is thought of as the "left and right" or horizontal axis while the y-axis is thought of as the "up and down" or vertical axis. In two dimensions, the coordinates x and y may lie anywhere in the interval (-∞, ∞), and an ordered pair (x, y) in two-dimensional Cartesian coordinates is often called a point or a 2-vector.

6-sphere coordinates | Cartesian geometry | coordinates | Helmholtz differential equation--Cartesian coordinates

elementary school level (California grade 4 standard)

René Descartes