Hair coloring uses dye to color human hair. It is most commonly used to transform gray hair to its previous color, to change hair color to a more desirable shade, or to return hair to its original color after hair dye has discolored it.

Hair coloring products are categorized based on the length of time they effect the colored hair. The four most common classifications are 'temporary', 'semi-permanent', 'demi-permanent', and permanent. Hair lightening products such as bleaches can be regarded as a sub-set of permanent hair coloring products.

Temporary hair color is available in various product forms including rinses, shampoos, gels, sprays, and others. This type of hair color is typically used to give brighter, more vibrant shades or colors.

Semi permanent hair color has no ammonia. They are great for hair that is damaged and fragile. A demi-permanent color is a gentle permanent color used whenever you want to deposit color without lifting the natural pigment but with the deep penetration results. Since they are gentle, they are perfect for tint-backs and color priming. They are also great for toning pre-lightened hair.

All permanent hair color products and lighteners contain both a developer or oxidizing agent and an alkalizing ingredient as part of their ammonia substitute. Permanent Color is best choice for gray hair coverage.