In the real world everything is in three-dimensional shape. You can just look around and observe! Even if you look sideways, a flat laminate has some thickness. An edge of your hair or a large size bus, all of them have three dimensional geometry. And it is necessary to learn their qualities. Therefore, start by understanding the lines, planes and angles from the topics given below.

Coordinate axes and coordinate planes in three dimensions. The coordinates of a point. Distance

Between the two points and the section formula.