The first writing surface was made in ancient Egypt from a plant called Papyrus, the royal plant of Egypt. The core of the papyrus plant was cut into tissue-thin strips, then laid across each other and pressed together under pressure. This turned the strips into a thin, smooth and durable laminated material that wasn’t quite paper.
Bristol generally describes a drawing paper that is pasted to form multi-ply sheets. Bristol sheets provide a stiff, strong surface to work on without the need for mounting. The term Bristol derives from the early days of European papermaking when mills would send their finest papers to Bristol, England to be pasted together. Bristol papers generally have two types of surfaces: smooth and vellum.
The selection of paper for shading techniques is influenced by the type of pencil used, the degree of darkness desired, the shading technique used, and the expression of the shading technique desired.
The key is to select a paper surface (medium or smooth) based upon the effects you’re looking to achieve. As a general rule, a medium or textured surface will be able to produce a more even, luminescent shade than a smooth surface.