Tan lines

A tan line is a visually clear division on the human skin between an area of pronounced comparative paleness relative to other areas that have been suntanned by exposure to ultraviolet (UV) radiation. The source of the radiation may be the sun, or artificial UV sources such as tanning lamps. Tan lines are usually an inadvertent result of a work environment or of recreational activities, but are sometimes intentional. Many people regard visible tan lines as un-aesthetic, and seek to avoid tan lines that will be visible when regular clothes are worn.

A "farmer's tan" (also called "golfer's tan" or "tennis tan") refers to the typical tan lines developed by regular outdoor activity. The farmer's tan is usually started with a suntan covering the exposed parts of the arms and neck. It is distinct in that the shoulders, chest, and back remain unaffected by the sun. Tennis and golf additionally cause recognizable tans on the middle section of the legs, due to the wearing of shorts and socks for prolonged hours in the sun.

The "Texas tan" is similar, with the exception that the shoulders are also affected by the sun, caused by working outdoors while wearing a sleeveless shirt.

Some of the common tan lines associated with a farmer's tan include:

A "driver's tan" (or similar terms such as "trucker's tan" or "taxi driver's arm") is a tanning pattern where one arm from the sleeve downward is tanned significantly more than the other arm, due to extensive driving of a motor vehicle with the window down.

A "sandal tan" is a set of distinctive tan lines on the feet, resulting from the straps of sandals worn throughout the summer by such different professions as lifeguards and monks.

Wearing a bikini in the sun results in the uncovered skin becoming suntanned and creates a "bikini tan". These tan lines separate pale breasts, crotch, and buttocks from otherwise tanned skin. "Racing stripes" may refer to the portion of a bikini tan line exposed when wearing one-piece swimwear.

A "biker's tan" is a tan line three-quarters up each leg, where lycra bike shorts would normally begin to cover. Depending on the activity, the inner side of the arms may be paler than the outer side. Unless the biker uses cycling gloves made to allow tanning, the area on the back of each hand will usually not be tanned.

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Wikipedia