C and D are points on the coordinate plane. To describe the position of any point, we use two numbers (x, y). x is called the x-coordinate and y is called the y-coordinate. x and y are called coordinates. x tells you the horizontal position from the origin. y tells you the vertical position from the origin. (x, y) is called an ordered pair. The coordinates of point C is (-3, -3). The coordinates of point D is (2, 4). The coordinates of the origin is always (0, 0).