The term loop, in its general sense, refers to something that closes back on itself. It has been used in the following particular applications:

• A loop is one of the fundamental structures used to tie knots. See Loop (knot).
• A loop is an aerobatic maneuver.
• In mathematics a loop is a quasigroup with an identity element. See Loop (algebra).
• In computer science, a loop is a sequence of commands that is carried out several times but written just once. See Program loop.
• In telecommunication, a loop is an electrical circuit that connects a telephone handset to the telephone exchange. See Loop (telecommunication).
• In music, a loop is a finite element of sound which is repeated by technical means. See music loop.
• Loop is also the name of a Shoegazing band. See Loop (band).
• The Loop is an area in downtown Chicago. See Loop (Chicago).
• In physics, a loop is an object in gauge theory, also called the Wilson loop.
• A loop is a type of inversion used in roller coasters. See Loop (roller coaster).
• A loop is a type of shuffling puzzle. See loop (puzzle).
• In rail transport, a loop can be used to turn trains around. See loop (rail).
• In the Interstate Highway system a loop is a road that forms a complete circle, such as Interstate 495 that encircles Washington DC, Arlington and Alexandria.
• LOOP is the Louisiana Offshore Oil Port.
• In figure skating, a loop is a kind of jump. See loop (jump).