A coordinate system is a reference framework used to describe the positions of objects like points, lines, and surfaces in a space. A fixed point called the origin is used as a reference in the coordinate system. The most common types of coordinate systems are one-, two-, or three-dimensional.

Number Line

A number line is a one-dimensional coordinate system. The origin represents the number 0. Negative numbers are placed along the line on the left-hand side of 0, while positive numbers are placed on the right-hand side of 0. Any real number can be graphed as a unique point on the number line.

Coordinate Plane

A coordinate plane, also known as a Cartesian or a rectangular coordinate system, is a two-dimensional coordinate system. It is a grid that results from intersecting a vertical number line with a horizontal number line at their zero points. The horizontal number line is usually named the x-axis and the vertical number line is usually the y-axis.

The positive numbers on the y-axis are above zero and the negative ones are below zero. The origin is where the lines intersect, which is the point (0,0). Every point on a coordinate plane is plotted according to its x- and y-coordinates.

Three-Dimensional Coordinate System

In a three-dimensional coordinate system, three axes intersect. Each axis is perpendicular to the other two axes. These axes are commonly labeled as the x-axis, the y-axis, and the z-axis. The origin of this system is the point (0,0,0) where the three axes intersect.

Note that in this case, the x-axis goes from front to back, the y-axis from left to right, and the z-axis from bottom to top. Any point in a three-dimensional system requires three coordinates called an ordered triple (x,y,z).