Direct dyes are a class of dyes, one of the two types of dyes that are mixed in ‘all purpose’ dyes such as Rit. (The other type in the mixture is an acid dye, which will not stay in any cellulose fiber for long.) The shades of direct dyes are duller than those provided by fiber reactive dyes and the wash fastness is poor while they may be more light fast.

Reactive dyes are a class of highly colored organic substances, primarily used for tinting textiles, which attach themselves to their substrates by a chemical reaction that forms a covalent bond between the molecule of dye and that of the fiber.