Terry Riley in the context of "Minimalism in music"

In visual arts, music, and other media, minimalism is an art movement that had emerged in the post-World War II era in Western art. It is often interpreted as a reaction to abstract expressionism and modernism. The movement anticipated various post-minimalist practices in contemporary art that extended or critically reflected on minimalism's original aims. Minimalism emphasized reducing art to its essentials, focusing on the object itself and the viewer's experience with minimal mediation from the artist. Prominent artists associated with minimalism include Donald Judd, Agnes Martin, Dan Flavin, Carl Andre, Robert Morris, Anne Truitt, and Frank Stella.

Minimalism in music features methods like repetition and gradual variation, such as the works of La Monte Young, Terry Riley, Steve Reich, Philip Glass, Julius Eastman and John Adams. The term is sometimes used to describe the plays and novels of Samuel Beckett, the films of Robert Bresson, the stories of Raymond Carver, and the automobile designs of Colin Chapman. In recent years, minimalism has come to refer to anything or anyone that is spare or reduced to its essentials.

Minimal music (also called minimalism) is a form of art music or other compositional practice that employs limited or minimal musical materials. Prominent features of minimalist music include repetitive patterns or pulses, steady drones, consonant harmony, and reiteration of musical phrases or smaller units. It may include features such as phase shifting, resulting in what is termed phase music, or process techniques that follow strict rules, usually described as process music. The approach is marked by a non-narrative, non-teleological, and non-representational approach, and calls attention to the activity of listening by focusing on the internal processes of the music.

The approach originated on the West Coast of the United States in the late 1950s and early 1960s, particularly around the Bay Area, where La Monte Young, Terry Riley and Steve Reich were studying and living at the time. After the three composers moved to the East Coast, their music became associated with the New York Downtown music scene of the mid-1960s, where it was initially viewed as a form of experimental music called the New York Hypnotic School. In the Western art music tradition, the American composers Moondog, La Monte Young, Terry Riley, Steve Reich and Philip Glass are credited with being among the first to develop compositional techniques that exploit a minimal approach. The movement originally involved dozens of composers, although only five (Young, Riley, Reich, Glass, and later John Adams) emerged to become publicly associated with American minimal music; other lesser known pioneers included Dennis Johnson, Terry Jennings, Richard Maxfield, Pauline Oliveros, Phill Niblock, and James Tenney. In Europe, the music of Louis Andriessen, Karel Goeyvaerts, Michael Nyman, Howard Skempton, Éliane Radigue, Gavin Bryars, Steve Martland, Peter Michael Hamel, Henryk Górecki, Arvo Pärt and John Tavener exhibits minimalist traits.

The Compositions 1960 are a set of text-based musical pieces written in 1960 by composer La Monte Young. Building on the work of John Cage, these pieces are unique in their emphasis on performance art and unconventional actions, such as releasing a butterfly into the room (#5), building a fire in front of the audience (#2), or pushing a piano into a wall (Piano Piece for Terry Riley #1). These compositions have been described as calling into question the definition of music.

The Theatre of Eternal Music (later sometimes called The Dream Syndicate) was an avant-garde musical group formed by La Monte Young in New York City in 1962. The first group (1962–1964) of performers consisted of La Monte Young, Marian Zazeela, Angus MacLise, and Billy Name. From 1964 to 1966, it consisted of La Monte Young (voice, saxophone), Marian Zazeela (voice, lighting), John Cale (viola), and Tony Conrad (violin), with sometimes also Terry Riley (voice). Since 1966, Theatre of Eternal Music has seen many permutations and has included Garrett List, Jon Gibson, Jon Hassell, Rhys Chatham, Alex Dea, Terry Jennings, and many others, including some members of the various 1960s groups. The group's self-described "dream music" explored drones and pure harmonic intervals, employing sustained tones and electric amplification in lengthy, all-night performances.

Archival recordings of the group's influential mid-1960s performances remain in La Monte Young's archive. None have ever seen official release following a dispute over compositional credit between Young and the pair of Conrad and Cale. Nonetheless, a 1965 bootleg recording removed from the archive by Young's first archivist, Arnold Dreyblatt, was controversially released in 2000 by Table of the Elements in CD as Day of Niagara. Other bootlegs of Theatre of Eternal Music have appeared online via file-sharing sites.

Anthony Schmalz Conrad (March 7, 1940 – April 9, 2016) was an American video artist, experimental filmmaker, musician, composer, sound artist, teacher, and writer. Active in a variety of media since the early 1960s, he was a pioneer of both drone music and structural film. As a musician, he was an important figure in the New York minimalist scene of the 1960s, during which time he performed as part of the Theatre of Eternal Music (along with John Cale, La Monte Young, Marian Zazeela, Terry Riley, and others). He became recognized as a filmmaker for his 1966 film The Flicker. He performed and collaborated with a wide range of artists over the course of his career.

In C is a composition by Terry Riley from 1964. It is one of the most successful works by an American composer and a seminal example of minimalism. The score directs any number of musicians to repeat a series of 53 melodic fragments in a guided improvisation.

Terry Riley's 1968 recording of In C was added to the National Recording Registry in 2022. The piece inspired countless other composers, including Philip Glass, Steve Reich, John Adams, and Julius Eastman.

A Rainbow in Curved Air is the third album by American composer Terry Riley, released in 1969 on CBS Records. The title track consists of Riley's overdubbed improvisations on several keyboard and percussion instruments. The B-side "Poppy Nogood and the Phantom Band" is a saxophone-based drone piece featuring tape loops and edits, drawing on Riley's all-night improvisatory performances in the 1960s.

Riley's record deal with CBS was part of "Music of Our Time," a short-lived album series on American experimental music helmed by CBS employee David Behrman, who had also facilitated the release of Riley's 1968 album In C; these two were the most successful LPs in the series. The album subsequently influenced a number of rock and electronic productions.