A loop is generally something that closes back on itself such as a circle or ring.

In a movie projector, the loop refers to the slack portion of the film around the projector lens.

In animation, a loop is a sequence of drawings repeated over and over.

A loop drive in table tennis, "The Loop" is an extreme topspin drive that produces a loopy tragetory.

Loop antenna, a radio antenna composed of one or more turns of conductor

To "loop" is a term used in audio post production where an actor re-records his/her voice in a studio setting. This term is currently often replaced with the term "ADR" or Automated Dialogue Replacement. This is used when the original audio that was recorded on set was poor/damaged/lost etc. The term "loop" itself refers, as much of the film industry terminology does, to the old days where the actor was shown a continual film loop of the scene he/she was recording so that they would be able to synchronise their voice with the performance that was shot at an earlier date. Now looping or ADR is performed using computer software.

Loop (electricity), a closed circuit

Möbius strip

Feedback loop

The Loop, the downtown neighbourhood of Chicago, Illinois bounded by an elevated railway in the shape of a loop

Loop (figure skating), one of the compulsory figures

A loop in playboating, a maneuver where the kayaker does a full forwards flip in the air.

Loop (algebra), a quasigroup with an identity element

A loop is industry vernacular for short pornographic films, many times without sound. Most are cheaply made and of poor quality. Before the advent of home video, such films were typically viewed by a single person in a booth, and the film was "looped" so that it could be played repeatedly when activated by a coin payment slot or similar device.

An infinite loop is a sequence of instructions in a computer program which loops endlessly.

Loop (aircraft), an aerobatic maneuver

Loop ramp (road transport), an element of a cloverleaf interchange allowing left turns via a 270° right turn

List of cycles

Loop jump (figure skating), a jump that takes off from a back outside edge and lands on the same edge

Loop (roller coaster), the most basic of roller coaster inversions

Loop (topology), a path that starts and ends at the same point

Loop device (Unix), a device node that allows a file to be mounted on a directory

Loupe, a small magnifying glass used by jewelers, watchmakers, and other precision craftsmen

Music loop, a finite element of sound which is repeated by technical means

Loop (band), a London rock band

Wilson loop (physics), a closed path integral of the gauge field

Loop (education), to advance an elementary school teacher with his or her class

The Loop (TV series), a comedy television show on the FOX network

Cycle graph

Loop (graph theory), an edge that begins and ends on the same vertex

Louisiana Offshore Oil Port

Loop, Germany, a municipality in Schleswig-Holstein, Germany

Local loop (telecommunication), the link connecting the customer to the carrier

In the Loop, a public radio show

Loop (novel), a sequel to the Japanese horror novel Ring

Loop (telecommunication), sending a signal on a channel and receiving it back at the sending terminal

Loop Ash Records, a record label.

Loop (knot), one of the fundamental structures used to tie knots

Inner loop (disambiguation)

Loop (biochemistry), a flexible region in a protein's secondary structure

Loop route (road transport); see also Beltway

Loop (Texarkana), a loop proposed around Texarkana, Arkansas

Loops (musical ensemble), a contemporary musical ensemble from Australia

The Loop is a nickname given to the suburban St. Louis, MO entertainment district that is formally known as the Delmar Loop.

The Loop is a segment on Attack of the Show hosted by Kevin Pereira.

A platform for Videoart based in Barcelona, Spain. Panel discussions, a festival and fair are held every year in May (http://www.loop-barcelona.com LOOP Barcelona Website).