A typical illustration of a coordinate plane is divided vertically by the axis and horizontally by the axis into four equal parts called quadrants. These quadrants are named
fourth, starting in the upper right quadrant, proceeding in a counter-clockwise fashion. Quadrants are sometimes expressed in writing with the Roman numerals I, II, III, and IV.
When describing the location of a point, it is often helpful to note its quadrant. One way to do this is by graphing the point and noting its quadrant visually. Consider the sample point found in the second quadrant.
By observing the signs of the and coordinates of a point, its quadrant can be determined, even without graphing. Below is a visualization of the relationship between coordinate sign and point quadrant.
Note: points on the axes belong to both neighboring quadrants, and the origin belongs to all quadrants.