The Cylindrical projection wraps texture maps on a surface with a cylindrical shape. Cylindrical projections provide a quick way to map a texture on cylindrical-shaped surfaces without much distortion. However, the texture seams may be visible in the render, depending on the surface's shape. Figure 1 shows the result of using Cylindrical projection on various simple surfaces.
Figure 1: Several simple shapes using Cylindrical projections to map a Texture to their surface