A surface designed to tolerate being saturated and accept pigment. Watercolour paper is absorbent, its comes in different weights and also in different textures. There are 3 main textures of watercolour paper, Rough, Cold pressed, and hot pressed. Rough is the most textured of the 3, cold pressed is slightly less textured, and hot pressed is a relatively smooth surface. Each manufacturer tends to stick to universal weighs measured in pounds per square inch (lbs) or grams per square metre (gsm).