Permanent is just what it means. This makes a 'permanent' change in the pigment of the hair shaft. It does not wash out! It will fade in time, but cannot be simply removed to "bring back" your natural color. All hair that has been colored in this way has the natural color pigments irreversibly chemically altered. It can be removed, leaving the "altered" hairshaft pigments, which can be "corrective colored" back close to the original color. This is a job which should be left to the Pros Only! It can be one visit or many visits to the salon to try to correct a bad color job, it is expensive and is hard on the hair to varying degrees.
Single Process Color
Single Process Color Is The Only Permanent Color That Should Be Attempted By The Amateur! Single process means that the color is lifted and deposited in one step.
Semi-Permanent color is what it says it is, it can cover gray and go darker, but can not lighten. It lasts varying lengths of time depending on the product. Suitable for amateur colorists. Warning: Double Process (bleaching and toning to the desired color) should never be attempted by a home hair colorist!. This is definitely a pro-only process.
Deposit Only Color
Deposit Only color can only "Deposit" color into the hair, there are many varieties on the market for the home user. These are very "User Friendly'' and usually condition and color in one step. The very popular color "glazes or translucent" colors are among the easiest to start with to enhance your color. Most use a very low 3% peroxide to activate them . Some are capable of lifting or lightening one level. Professionally, Redken SHADES EQ is my favorite, bar none!