<P> In parallel projection, the lines of sight from the object to the projection plane are parallel to each other . Thus, lines that are parallel in three - dimensional space remain parallel in the two - dimensional projected image . Parallel projection also corresponds to a perspective projection with an infinite focal length (the distance from a camera's lens and focal point), or "zoom". </P> <P> Images drawn in parallel projection rely upon the technique of axonometry ("to measure along axes"), as described in Pohlke's theorem . In general, the resulting image is oblique (the rays are not perpendicular to the image plane); but in special cases the result is orthographic (the rays are perpendicular to the image plane). Axonometry should not be confused with axonometric projection, as in English literature the latter usually refers only to a specific class of pictorials (see below). </P> <P> The orthographic projection is derived from the principles of descriptive geometry and is a two - dimensional representation of a three - dimensional object . It is a parallel projection (the lines of projection are parallel both in reality and in the projection plane). It is the projection type of choice for working drawings . </P> <P> With multiview projections, up to six pictures (called primary views) of an object are produced, with each projection plane parallel to one of the coordinate axes of the object . The views are positioned relative to each other according to either of two schemes: first - angle or third - angle projection . In each, the appearances of views may be thought of as being projected onto planes that form a 6 - sided box around the object . Although six different sides can be drawn, usually three views of a drawing give enough information to make a 3D object . These views are known as front view, top view and end view . The terms elevation, plan and section are also used . </P>

What are the types of projection used in drawing