One point perspective has vanishing point.

Things get and vanish at the vanishing point because it's too to see.

After connecting of the front shape to VP, we draw lines to lines of the front shape for the layer.

Oblique projection has vanishing points.

Things get smaller if they are away.

After drawing lines from corners of the front shape to direction at degree angle, we draw lines parallel to lines of the front shape for the back layer.

Isometric projection has vanishing points.

Things get smaller if they are away.

It draws a subject's top, left, and right sides .

The base lines of the left and right sides are each other, forming an with the vertical axis.

Either the left or right side can become the view in oblique.

After drawing lines from corners of the front shape to the back at a degree angle from the line, we draw lines to lines of the front shape for the back layer.