Note: linear perspective drawing depends on the premise that we are viewing the world through a single, unmoving eye.
Picture plane: This is the imaginary flat surface between the viewer's eye and the scene or object being drawn.
Cone of vision: This describes the area of undistorted vision and is roughly 60 degrees wide. Anything outside the cone of vision would be distorted or blurred.
Station point (also called the "viewer's eye): The position of the eye
Center line of sight: (also called the Central Visual Ray) this imaginary line extends from the viewer's eye to the vanishing point
Horizon line: where sky and earth would appear to meet if the ground were perfectly flat. This also indicates the level of the viewer's eye
Ground Plane: the horizontal surface (ground or water) that the viewer is looking across.
Ground Line: This is the line parallel to the horizon line on which the object rests.
Vanishing point: The point along the horizon where parallel lines appear to converge
Orthogonal lines (aka foreshortened lines): The diagonal lines drawn along the edges of objects that recede to the vanishing point to create the illusion of distance