Athletic tape is used in a wide variety of sports primarily to provide support for a joint in order to prevent injury. The most common situation this form of tape is used is by an athlete that has been injured previously and wishes to prevent further injury.
Athletic tape is sturdy and acts to limit movement of a joint in order to protect it from excessive forces of movement that may lead to injury or re-injury.
Supportive taping in this fashion may be used in conditions that require it outside of a sporting environment.
"Kin"-tape, in quotes because there are many different brands, are also used to protect the body, but act in a different fashion. This form of taping acts on what is called proprioception. Proprioception is the body's awareness of its position in space. This sense comes from a combination of different inputs including your sense of balance, hearing, vision, and touch. It is this sense of touch that the tape acts on to alert the brain that a particular part of the body is entering the limits of normal movement.
This form of tape also works to help reduce swelling for various types of injuries by promoting proper flow of fluids through the part of the body it is interacting with.