Hair colors are dyes which are used to color human hair. Hair colors are categorized on the basis of time period for which they effect the colored hair. Hair Colors make use of natural agents and synthetic dyes to produce different coloring effects. The most common division of colors are temporary, half permanent, deposit colors, and permanent.
Colors that are temporary
The color does not enter the hair; instead it only coats the hair which can be removed by using shampoo. The strength of color can be improved by using bleach, before the applying hair color. Temporary color is used for more glowing colors such as orange or red.
Colors that are half permanent
These colors deposit color on hair without lightening it. These colors enter the hair. They last longer than temporary hair colors.
Colors that can be deposited
Deposit colors are used whenever we want to deposit color without removing the natural pigment but the results are same as permanent hair colors.
Colors that are permanent
These colors go deep into the hair. These colors remove the natural pigment and take their place instead.

Hair colors are applied onto hair in two main ways: One of them being, that color is applied to all hair on the head, to get a uniform effect. The other one is that dye is applied to selected sections of hair, to produce streaks. Colors are used to make hair look more attractive. Colors are used to give hair different looks such as natural look including colors like black, blond, red, brown etc. and artificial look including colors like fuchsia. Hair colors make use of chemicals which remove the natural color molecules found inside the hair and replace them with the applied color.

Sometimes even after using good branded colors and dyes, the user does not get the results that he/she desired. This can happen for a number of reasons such as:
• Trying to color already colored hair.
• Trying to lighten or darken the shade of the color without letting the color dry properly.
• Earlier use of henna, which can react with dyes and produce different color combinations.
So it is advised to wash hair thoroughly before dying the hair.
Chemicals are used to derive colors that the user demands. The chemicals used in these colors have their own ill effects. These chemicals in some cases cause skin irritation, allergy, breakage of hair and tarnishing of skin as well. Hair colors can lead to more serious health problems such as lead poisoning. Recent studies have found chemicals, used in dyes, to be toxic. Studies are also going on to check if there is any relation between development of cancer and the use of hair color.

We can also use natural coloring agents such as henna, amla, turmeric and senna. These might not be as long lasting as the chemical dyes but these agents are much safer than chemical dyes.