A hair clipper (often individually known by the apparent plural hair clippers in a similar way to scissors) is a specialised implement used to cut human head hair. They work on the same principle as scissors, but are distinct from scissors themselves and razors.
Hair clippers comprise a pair of sharpened comb-like blades in close contact one above the other and the side which slide sideways relative to each other, a mechanism which may be manual or electrical to make the blades oscillate from side to side, and a handle. The clipper is moved so that hair is positioned between the teeth of the comb, and cut with a scissor action when one blade slides sideways relative to the other. Friction between the blades needs to be as low as possible, which is attained by choice of material and finish, and frequent lubrication.
Electric hair clippers are driven by an electric motor which makes the blades oscillate from side to side. They have gradually displaced manual hair clippers in many countries. Three different motor types are used in clipper production: magnetic, rotary and pivot. Rotary style may be driven by direct current or alternating current electricity source. Both magnetic and pivot style clippers use magnetic forces derived from winding copper wire around steel. Alternating current creates a cycle attracting and relaxing to a spring to create the speed and torque to drive the clipper cutter across the combing blade. Leo J. Wahl invented the first electric hair clipper.
Electric hair clipper blades must be lubricated frequently. Each major hair clipper manufacturer sells its own brand of hair clipper oil. Clippers can also be maintained with aerosol clipper spray which acts as a coolant, disinfectant, lubricant, cleaner, and rust preventative. .