Hair is often referred to as the woman's “crowning glory”. The hair occupies the largest area on a person's face, so it is no wonder that women have tried to do all sorts of things with their hair to make them look more attractive. Hair is cut, styled, permed, colored and even shaved. Perming and hair color are the two most important categories of the hair cosmetics business and the pillars of the beauty salon industry. Annual trade shows like Cosmoprof are held to showcase the recent developments and trends in the hairdressing industry and hair color is among the top attractions.

Depending on a person's ethnicity, hair is either black, brown, blonde or red. This has given rise to people wanting to change their hair color for social or cosmetic reasons. Hair color is usually done in beauty salons, although many hair color brands are now available in retail shops for people who want to color their hair at home. This has motivated beauty salons to look for more artistic ways to do hair coloring and provide women with a service not available on a do-it-yourself basis.

There are three types of hair coloring: permanent, semi-permanent and temporary. Permanent hair color makes use of hair dye mixed with ammonia to open up the hair's cuticle layers and deposit the dye in the cortex of the hair. Semi-permanent hair color, mostly with a minimal level of ammonia, deposits the dye in the cuticle layer where it stays for a while and washes away after a week or two. Temporary hair color is deposited on the outside of the hair shaft and can be rinsed out with every shampoo.

Hair color is available generally in cream or liquid form. Cream hair color must be applied by hand using a tinting brush. Traditionally, people have had their hair colored to cover gray hair. Today, however, a popular form of hair coloring is “highlighting” In this process, the hairdresser colors certain strands of the hair to produce highlights or lowlights for subtle or dramatic cosmetic effect.

The airbrush is a valuable tool in highlighting. A Gravity Feed, Single-Action internal mix airbrush is best suited for this job. Hair is first shampooed and dried. If the client wishes to have a lighter hair color, the hair has first to be bleached to remove the natural hair color. Depending upon how long the client wishes the new hair color to last, liquid hair color of the proper type – permanent, semi-permanent or temporary - is chosen.  The hairdresser then picks out the strands to be colored and airbrushes the color onto the strands. After the hair has been colored, a conditioner is applied to set the color. The airbrush gives the hairdresser the advantage of applying the color quickly and evenly. It also enables the hairdresser to draw temporary designs on the hair – a favorite among teens and young adults nowadays.

The hair color industry is in a continual state of flux. Because hair color use dyes, governments especially the European Union are actively trying to establish the safety of the dyestuffs used in hair colors, leading companies to continually develop new raw materials to comply with ever changing regulations. The application of hair color, however, remains unchanged and will probably stay the same way as long as people's hair and hairstyles remain the way they are.