Projection general

Projection is the process of flattening a three dimensional surface to form a plane. In other words, it is the representation of the surface of the earth as a flat surface.
Different projections have been developed for transferring information from a sphere to a plane, and each distorts the data in different ways.
The projections are:
Firstly, the Conic projection which includes the Simple conic projection, the Lambert conformal projection and the polygonal projection.
Secondly, the azimuthal projection which includes the gnomonic, the stereographic and the orthographic projection.
And thirdly, the cylindrical projection which includes the Mercator, the transverse and the oblique Mercator projection.