# Loop

Loop or LOOP may refer to:

## Brands and enterprises

* Loop (mobile), a Bulgarian virtual network operator and co-founder of Loop Live
* Loop, clothing, a company founded by Carlos Vasquez in the 1990s and worn by Digable Planets
* Loop Mobile, an Indian mobile phone operator
* Loop, a reusable container program announced in 2019 by TerraCycle

## Geography

* Loop, Germany, a municipality in Schleswig-Holstein
* Loop (Texarkana), a roadway loop around Texarkana, Arkansas, United States
* Loop, Blair County, Pennsylvania, United States
* Loop, Indiana County, Pennsylvania, United States
* Loop, West Virginia, United States
* Loop 101, a semi-beltway of the Phoenix Metropolitan Area
* Loop 202, a semi-beltway of the Phoenix Metropolitan Area
* Loop 303, a semi-beltway of the Phoenix Metropolitan Area
* Chicago Loop, the downtown neighborhood of Chicago bounded by the elevated railway The Loop
** Loop Retail Historic District, a shopping district in the Chicago Loop
* Delmar Loop, an entertainment district in St. Louis, Missouri
* London Outer Orbital Path (LOOP), a signed walk around the edge of Outer London, England
* Louisiana Offshore Oil Port (LOOP), a deep-water port in the Gulf of Mexico off the coast of Louisiana

## People

* Call Me Loop (born 1991), English singer and songwriter
* Liza Loop (active from 1975), American technology pioneer
* Uno Loop (1930–2021), Estonian singer, musician, athlete, actor, and educator
* Victoria Loop, brass and guitar player with English band Half Man Half Biscuit

## Arts, entertainment, and media
### Film

* Loop (1991 film), a British romantic comedy
* Loop (1999 film), a Venezuelan film
* Loop (2020 film), an American animated short
* Film loop, the slack portion of the film around the projector lens in a movie projector
* Porn loop, an 8 or 16 mm video "short" of a pornographic nature that could be purchased from men's magazines starting in the 1950s

### Music
#### Groups

* Loop (band), a London rock band

#### Other uses in music

* Loop (album), a 2002 album by Keller Williams
* Loop (music), a finite element of sound which is repeated by technical means
* "Loop" (Maaya Sakamoto song), 2005
* "Loop" (Sarah Bonnici song), the entry for Malta in the Eurovision Song Contest 2024
* Loop, a 2020 mini-album by Peakboy

### Other uses in arts, entertainment, and media

* Loop (novel), a novel in the Ring series by Koji Suzuki
* LOOP Barcelona, an annual meeting point for video art in Barcelona, Spain

## Computing and technology

* Loop (computing), a method of control flow in computer science
* LOOP (programming language), the pedagogical primitive recursive programming language with bounded loops
* Loop (telecommunication), sending a signal on a channel and receiving it back at the sending terminal
* Audio induction loop, an aid for the hard of hearing
* Local loop, the physical link in telephony that links the customer premises to the telephone company (telco)
* Loop device, a Unix device node that allows a file to be mounted as if it were a device
* LOOPS, the object system for Interlisp-D
* continue statement (in some languages skip, cycle, next, loop, or iterate), a structured control statement that skips ahead to the next iteration of the loop containing it
* Microsoft Loop, collaborative software

## Mathematics

* Loop (algebra), a quasigroup with an identity element
* Loop (graph theory), an edge that begins and ends on the same vertex
* Loop (topology), a path that starts and ends at the same point, possibly reduced to a single point

## Sports

* Aerobatic loop, a type of aerobatic maneuver
* Ground loop (aviation), a rapid horizontal (yawing) rotation of a fixed-wing aircraft used in emergencies to bleed of energy while landing
* Loop, a type of canoe freestyle maneuver
* Loop (cricket), an aspect of bowling in cricket
* Loop jump, a figure skating jump
* Loop, a type of offensive shot in table tennis

## Roller coasters

* Loop (roller coaster), a basic roller coaster inversion
* Pretzel loop, a roller coaster element

## Transportation

* Loop (Amtrak train), a discontinued Amtrak train
* The Loop (CTA), a rapid transit section bounding Chicago's Loop neighborhood
* Loop, underground public transportation system of The Boring Company in Tesla cars, including a proposed DC-to-Baltimore system
* Balloon loop, a section of track that allows reversal of direction without stopping
* Circle route, a public transport route that travels around and connecting the peripheral zones of an area.
* Loop line (railway), a branch line that deviates from a direct route and rejoins it at another location
* Loop route, a main route or highway that forms a closed loop
* Passing loop, a short section of track that allows trains to pass on a single track route
* Ring road or loop, a main route or highway that encircles a town or city
* Spiral (railway), a section of track that allows a train to climb a steep hill

## Other uses

* Compulsion loop, a habitual chain of activities that will be repeated by the user to cause them to continue the activity
* Loop (biochemistry), a flexible region in a protein's secondary structure
* Loop (education), the process of advancing an elementary school teacher with his or her class
* Loop (knot), one of the fundamental structures used to tie knots
* Loop, the end of some dead-end streets
* Loop, a type of fingerprint pattern