Hair coloring

Hair coloring, or hair dyeing, is the practice of changing the color of the hair on humans' heads. The main reasons for this are cosmetic: to cover gray or white hair, to alter hair to create a specific look, to change a color to suit preference or to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching.

Hair coloring can be done professionally by a hairdresser or independently at home. Hair coloring is very popular, with 50-80% of women in the United States, Europe, and Japan having reported using hair dye. At-home coloring in the United States reached sales of $1.9 billion in 2011 and was expected to rise to $2.2 billion by 2016.