Hashish, often known as "hash", is a cannabis preparation composed of compressed stalked resin glands, called trichomes, collected from the unfertilized buds of the cannabis plant. It contains the same active ingredients but in higher concentrations than unsifted buds or leaves. Hashish is often a paste-like substance with varying hardness and pliability, its color most commonly light to dark brown but varying toward green, yellow, black or red.^{[citation needed]}

Hashish is heated in a pipe, hookah, bong, bubbler, vaporizer, hot knife, smoked in joints mixed with cannabis buds or tobacco (the latter being more common in Europe and Africa), or cooked in foods.