1. We require two perpendicular axes to locate a point in the plane. One of them is horizontal and other is Vertical.
2. The plane is called Cartesian plane and axis are called the coordinates axis.
3. The horizontal axis is called x-axis and Vertical axis is called y-axis.
4. The point of intersection of axis is called origin.
5. The distance of a point from y axis is called x–coordinate or abscissa and the distance of the point from x –axis is called y– coordinate or Ordinate.
6. The Origin has zero distance from both x-axis and y-axis so that its abscissa and ordinate both are zero. So the coordinate of the origin is (0,0).
7. A point on the x–axis has zero distance from x-axis so coordinate of any point on the x-axis will be (x, 0).
8. A point on the y–axis has zero distance from y-axis so coordinate of any point on the y-axis will be (0, y).
9. The axes divide the Cartesian plane into four parts. These Four parts are called the quadrants