Dyeing is the process of changing the colour of a yarn or cloth by treatment with a dye. Dyeing is used by humans to decorate fabrics. The primary source of dye is nature, with the dyestuff being extracted from animals or plants.
In the last two centuries, humans have produced artificial dyes to achieve specific colors, and to render the dyes fast, so that they do not run when the material is washed. Dyes are applied to material by direct application, or by immersing the yarn or cloth in the liquid dye or a solution of the dye. In order to remove natural or unwanted color from the material, the opposite process of bleaching is carried out.
Indian dyers had mastered the art of dyeing with fast colors from ancient times. They were considered magicians by travelers, who saw them putting a white cloth into a pale liquid of indigo dye and when the cloth appeared from the dye bath it was still white. It was only when it came into contact with oxygen and it became blue. Multiple immersions and exposure to the air enriched the color. People felt this was a magical makeover. Printed fabrics were in regular use throughout North India, as well as for home use. They also became essential export items.