Progressive rock in the context of "Emerson, Lake "

Jazz fusion (also known as jazz rock, jazz-rock fusion, or simply fusion) is a popular music genre that developed in the late 1960s when musicians combined jazz harmony and improvisation with rock music, funk, and rhythm and blues. Electric guitars and basses, amplifiers, and keyboard instruments (including electric pianos and organs) that were popular in rock began to be used by jazz musicians, particularly those who had grown up listening to rock and roll.

Jazz fusion arrangements vary in complexity. Some employ groove-based vamps fixed to a single key or a single chord with a simple, repeated melody. Others use elaborate chord progressions, unconventional time signatures, or melodies with counter-melodies, in a similar fashion to progressive rock. These arrangements, whether simple or complex, typically include improvised sections that can vary in length, much like in other forms of jazz.

Throughout the history of the British Isles, the land that is now the United Kingdom has been a major music producer, drawing inspiration from church music and traditional folk music, using instruments from England, Scotland, Northern Ireland, and Wales. Each of the four countries of the United Kingdom has its own diverse and distinctive folk music forms, which flourished until the era of industrialisation when they began to be replaced by new forms of popular music, including music hall and brass bands. Many British musicians have influenced modern music on a global scale, and the UK has one of the world's largest music industries. English, Scottish, Irish, and Welsh folk music as well as other British styles of music heavily influenced American music such as American folk music, American march music, old-time, ragtime, blues, country, and bluegrass. The UK has birthed many popular music genres such as beat music, psychedelic music, progressive rock/pop, heavy metal, new wave, industrial music, and drum 'n' bass.

In the 20th century, influences from the music of the United States, including blues, jazz, and rock and roll, were adopted in the United Kingdom. The "British Invasion"—spearheaded by Liverpool band the Beatles, often regarded as the most influential band of all time—saw British rock bands become highly influential around the world in the 1960s and 1970s. Pop music, a term which originated in Britain in the mid-1950s as a description for "rock and roll and the new youth music styles that it influenced", was developed by British artists like Black Sabbath, the Beatles and the Rolling Stones, whom among other British musicians led rock and roll's transition into rock music.

The album era (sometimes, album-rock era) was a period in popular music, usually defined as the mid-1960s through the middle of the 2000s decade, in which the album—a collection of songs issued on physical media—was the dominant form of recorded music expression and consumption. It was driven primarily by three storage formats: the 33⅓ rpm long-playing record (LP), the cassette tape, and the compact disc (CD). Rock musicians from the United States and the United Kingdom were often at the forefront of the era. The term "album era" is also used to refer to the marketing and aesthetic period surrounding a recording artist's release of an album.

Long-playing record albums, first released in 1948, offered the ability to sell larger amounts of music than singles. The album era arrived in earnest in the mid-1960s, when the Beatles began to release artistically ambitious and top-selling LPs. The industry embraced albums to immense success, and burgeoning rock criticism validated their cultural value. By the 1970s, the LP had emerged as a fundamental artistic unit and a widely popular item with young people. Some were concept albums, especially by progressive musicians in rock and soul.

The Hammond organ is an electric organ invented by Laurens Hammond and John M. Hanert, first manufactured in 1935. Multiple models have been produced, most of which use sliding drawbars to vary sounds. Until 1975, sound was created from rotating a metal tonewheel near an electromagnetic pickup, and amplifying the electric signal into a speaker cabinet. The organ is commonly used with the Leslie speaker.

Around two million Hammond organs have been manufactured. The organ was originally marketed by the Hammond Organ Company to churches as a lower-cost alternative to the wind-driven pipe organ, or instead of a piano. It quickly became popular with professional jazz musicians in organ trios—small groups centered on the Hammond organ. Jazz club owners found that organ trios were cheaper than hiring a big band. Jimmy Smith's use of the Hammond B-3, with its additional harmonic percussion feature, inspired a generation of organ players, and its use became more widespread in the 1960s and 1970s in genres such as rhythm and blues, rock (especially progressive rock), and reggae.

A pedalboard (also called a pedal keyboard, pedal clavier, or, with electronic instruments, a bass pedalboard) is a keyboard played with the feet that is usually used to produce the low-pitched bass line of a piece of music. A pedalboard has long, narrow lever-style keys laid out in the same semitone scalar pattern as a manual keyboard, with longer keys for C, D, E, F, G, A, and B, and shorter, raised keys for C♯, D♯, F♯, G♯ and A♯. Training in pedal technique is part of standard organ pedagogy in church music and art music.

Pedalboards are found at the base of the console of most pipe organs, pedal pianos, theatre organs, and electronic organs. Standalone pedalboards such as the 1970s-era Moog Taurus bass pedals are occasionally used in progressive rock and fusion music. In the 21st century, MIDI pedalboard controllers are used with synthesizers, electronic Hammond-style organs, and with digital pipe organs. Pedalboards are also used with pedal pianos and with some harpsichords, clavichords, and carillons (church bells).

Psychedelic music (sometimes called psychedelia) is a wide range of popular music styles and genres influenced by 1960s psychedelia, a subculture of people who used psychedelic drugs such as DMT, LSD, mescaline, and psilocybin mushrooms, to experience synesthesia and altered states of consciousness. Psychedelic music may also aim to enhance the experience of using these drugs and has been found to have a significant influence on psychedelic therapy.

Psychedelia embraces visual art, movies, and literature, as well as music. Psychedelic music emerged during the 1960s among folk and rock bands in the United States and the United Kingdom, creating the subgenres of psychedelic folk, psychedelic rock, acid rock, and psychedelic pop before declining in the early 1970s. Numerous spiritual successors followed in the ensuing decades, including progressive rock, krautrock, and heavy metal. Since the 1970s, revivals have included psychedelic funk, neo-psychedelia, and stoner rock as well as psychedelic electronic music genres such as acid house, trance music, and new rave.

Progressive pop is pop music that attempts to break with the genre's standard formula, or an offshoot of the progressive rock genre that was commonly heard on AM radio in the 1970s and 1980s. It was originally termed for the early progressive rock of the 1960s. Some stylistic features of progressive pop include hooks and earworms, unorthodox or colorful instrumentation, changes in key and rhythm, experiments with larger forms, and unexpected, disruptive, or ironic treatments of past conventions.

The movement started as a byproduct of the mid-1960s economic boom, when record labels began investing in artists and allowing performers limited control over their own content and marketing. Groups who combined rock and roll with various other music styles such as Indian ragas and Asian-influenced melodies ultimately influenced the creation of progressive rock (or "prog"). When prog records began declining in sales, some artists returned to a more accessible sound that remained commercially appealing until the 1990s.

Black Sabbath were an English heavy metal band formed in Birmingham in 1968 by guitarist Tony Iommi, drummer Bill Ward, bassist Geezer Butler and vocalist Ozzy Osbourne. After adopting the Black Sabbath name in 1969 (the band were previously named Polka Tulk Blues Band and then Earth), they distinguished themselves through occult themes with horror-inspired lyrics and down-tuned guitars. Their first three albums, Black Sabbath, Paranoid (both 1970), and Master of Reality (1971), were commercially successful, and are cited as pioneering albums in the development of heavy metal. Subsequent albums Vol. 4 (1972), Sabbath Bloody Sabbath (1973), Sabotage (1975), Technical Ecstasy (1976), and Never Say Die! (1978) saw the band explore more experimental and progressive styles.

Osbourne was fired from Black Sabbath in 1979 and replaced by former Rainbow vocalist Ronnie James Dio, who recorded three albums with the band, Heaven and Hell (1980), Mob Rules (1981), and their first authorised live album Live Evil (1983), the last two featuring drummer Vinny Appice replacing Ward. Following Dio and Appice's departures, Iommi and Butler recorded Born Again (1983) with Ward returning on drums, and Ian Gillan, then-formerly of Deep Purple, on vocals. By 1984, Butler, Ward, and Gillan had all departed, leaving Iommi to assemble a new version of Black Sabbath. For the next thirteen years, the band endured many personnel changes that included vocalists Glenn Hughes (another former Deep Purple member, who sang on Black Sabbath's 1986 album Seventh Star) and Tony Martin, as well as several bassists and drummers. Of the vocalists during these years, Martin's tenure was the longest, joining in 1987 and recording three albums – The Eternal Idol (1987), Headless Cross (1989), and Tyr (1990) – before his initial departure in 1991. That same year, Iommi reunited with Butler, Dio and Appice to record Dehumanizer (1992), though Dio and Appice both departed again by the end of 1992. Martin returned for two more studio albums, Cross Purposes (1994) and Forbidden (1995), and one live album, Cross Purposes Live (1995), before the band went on a one-year hiatus.

Pub rock is a subgenre of rock music that emerged in the early to mid-1970s in the United Kingdom. A back-to-basics movement, which incorporated roots rock, pub rock was a reaction against the expensively-recorded and produced progressive rock and flashy glam rock scenes at the time. Although short-lived, pub rock was played live in small traditional venues like pubs and clubs. Since major labels showed no interest in pub rock groups, pub bands sought out independent record labels such as Stiff Records. Indie labels used relatively inexpensive recording processes, so they had a much lower break-even point for a record than a major label.

With pub rock's emphasis on small venues, simple, fairly inexpensive recordings and indie record labels, it was the catalyst for the development of the British punk rock scene. Despite these shared elements, though, there was a difference between the genres: while pub rock harked back to early rock and roll and R&B, punk was iconoclastic, and sought to break with the past musical traditions.