Plato divided literature into the three classic genres accepted in Ancient Greece: poetry, drama, and prose. Poetry is further subdivided into epic, lyric, and drama. The divisions are recognized as being set by Aristotle and Plato; however, they were not the only ones. Many genre theorists added to these accepted forms of poetry.
Genre; from French genre, "kind" or "sort", from Latin genus, Greek is any category of literature, music, or other forms of art or entertainment, whether written or spoken, audio or visual, based on some set of stylistic criteria. Genres form by conventions that change over time as new genres are invented and the use of old ones is discontinued. Often, works fit into multiple genres by way of borrowing and recombining these conventions.
Genre began as an absolute classification system for ancient Greek literature. Poetry, prose, and performance each had a specific and calculated style that related to the theme of the story. Speech patterns for comedy would not be appropriate for tragedy, and even actors were restricted to their genre under the assumption that a type of person could tell one type of story best. In later periods genres proliferated and developed in response to changes in audiences and creators. Genre became a dynamic tool to help the public make sense out of unpredictable art. Because art is often a response to a social state, in that people write/paint/sing/dance about what they know about, the use of genre as a tool must be able to adapt to changing meanings.
Genre suffers from the same ills of any classification system. Genre is to be reassessed and scrutinized, and to weigh works on their unique merit. It has been suggested that genres resonate with people because of the familiarity, the shorthand communication, as well as the tendency of genres to shift with public mores and to reflect the zeitgeist. While the genre of storytelling has been relegated as lesser form of art because of the heavily borrowed nature of the conventions, admiration has grown. Proponents argue that the genius of an effective genre piece is in the variation, recombination, and evolution of the codes.
Music comes from everywhere, and so do the names we call it by. There's a longstanding cliche that only the music business needs genre names – everyone else either likes it or they don't. That is, of course, bunk, as anyone who's heard enough people trot out lines such as "I like all music except for rap and country" is aware. Not least because quite a lot of those genre names come from the artists themselves.
Gospel, for example, was more or less invented by Rev Thomas A Dorsey. As Georgia Tom, Dorsey played jazz and blues piano before turning to the Bible for inspiration in 1932 and selling songs such as Precious Lord, Take My Hand to churches in Chicago, then across America. His group's name was the University Gospel Singers. Similarly, bluegrass originates from the name of the country singer and mandolinist Bill Monroe's backing band from 1938 to his 1996 death: the Blue Grass Boys. They were named after Monroe's native Kentucky, "the Blue Grass State". Glitter rock – a synonym for glam – comes from Gary Glitter, about which the less said, the better.
More often, a genre name will come from a musician's works. Free jazz comes from Ornette Coleman's 1960 album of the same name; ditto blue-eyed soul, from the Righteous Brothers' 1963 LP. The mid-60s Jamaican boogie dubbed rocksteady is named for an 1966 Alton Ellis single, while reggae followed it into Jamaican dance-halls on the heels of the Maytals' Do the Reggay in 1968. Soca is a condensation of Trinidadian artist Lord Shorty's Soul of Calypso, from 1974, while acid house, originally from Phuture's 1987 single Acid Tracks, has come to mean anything with a yammering, squealing TB-303 on it.
Ambient, of course, comes from Brian Eno's Ambient 1: Music for Airports (1978). Eno says in his famous liner notes from 1975's Discreet Music that the idea had come to him while recuperating in hospital after getting hit by a car in January 1975; a guest put 18th-century harp music on at low volume, then left the immobile Eno to ponder its placement. The guest remembers it differently: in Geeta Dayal's Another Green World, Eno's then-girlfriend Judy Nylon says she put the harp music on intending to balance it with the pouring rain outside, and that Eno caught on immediately.
Sometimes lyrics become genres. Doo-wop comes from any number of primordial R&B harmony vocal-group records – the two most obvious are the Turbans' 1955 When You Dance ("Doo-wop, de-doo-doo," runs the end of the refrain) and the Five Satins' In the Still of the Nite a year later (under the sax solo, the chant "Doo-bop, doo-bah!"). In the late '60s, New York oldies radio DJ Gus Gossert put it into wide use, though he claimed he got it from California aficionados.
The term jungle came from a sound system yard tape from Jamaica that featured the chant "Alla the junglists". MC Navigator of pirate station Kool FM told critic Simon Reynolds in his book Energy Flash: "There's a place in Kingston called Tivoli Gardens, and the people call it the Jungle." When Rebel MC sampled it, breakbeat-led house had a new name. Reynolds points out that the British rave label Ibiza had "the first use of the word 'jungle' on their (12-inch) sleeves", including 1991's Noise Factory single, Jungle Techno.
Sometimes record labels become genre names, as with industrial, named after Throbbing Gristle's imprint, established in 1976, and lovers rock, industrials polar opposite: sentimental, romantic reggae named for the London label of Dennis and Eve Harris from around the same time. And sometimes record labels just mandate new terms. Outlaw country, no wave and Techno all came into use via compilation albums: respectively, 1976's Wanted! The Outlaws (featuring Willie Nelson, Waylon Jennings, Jessi Colter, and Tompall Glaser); 1978's No New York (Teenage Jesus & the Jerks, Contortions, Mars and DNA); 1988's Techno! The New Dance Sound of Detroit (Juan Atkins, Derrick May, and Kevin Saunderson).
There are occasions, too, when an artist just says something is something, and that is that. Think of Afrobeat – not be confused with Afropop, an old catch-all to describe, well, all pop from Africa. Afrobeat was the name coined in 1968 by Fela Kuti to describe the music he was inventing around that time, made up of funk, jazz, Nigerian high-life, anti-authoritarian lyrics and high-grade weed.
The 90s were rife with musician-coined genres. Riot grrrl was the name of a 1991 fanzine put together by four of that music's key players: Allison Wolfe and Molly Neuman of Bratmobile; Kathleen Hanna and Tobi Vail of Bikini Kill. Illbient was coined in 1994 by DJ Olive, of the trio We, to describe a multimedia presentation to a journalist in Brooklyn. "Some older man who said he was a journalist asked me if this was ambient music," Olive says, "and I blurted out as a joke, 'Nope, this is illbient.' We all had a laugh about it." And in 1996, producers Ed Rush and Trace of the No U Turn label minted the phrase techstep to describe their blaring, dense, hard-as-hell style of drum and bass.
But sometimes an artist assigns a title that becomes something else. Power-pop was coined by Pete Townshend in 1967 to define the Who, but wound up being what Eric Carmen of prime power-pop practitioners the Raspberries described as "groups that came out in the 70s that played kind of melodic songs with crunchy guitars and some wild drumming". Not to mention the endless acolytes who mimicked them.
Often, technology drives musical changes, so equipment plays its role, too. Acid, noted above, is one example. So is dub, short for the "dubplate" (duplicate platter) Jamaican sound system operator Ruddy Redwood ordered in late 1967 from Duke Reid's pressing plant. The recording was On the Beach by the Paragons, and the engineer, Byron Smith, accidentally wiped the vocal. Reid played it alongside the vocal version; the response was so strong he began putting instrumentals on the B-sides. Eventually, creative engineers such as King Tubby and Lee Perry would take the dub side into whole new areas of bass-heavy abstraction.
Of course, journalists need these terms more than anyone, in a sense – a recognizable genre name is powerful shorthand. As the longtime bible of the American music industry, thanks to its trend-setting album and single charts, Billboard has played a significant role in disseminating musical titles. Easy listening, for instance, was coined in the 17 July 1961 edition (not, sadly, included on the magazine's Google Books archive, though every other 1961 issue is). Rhythm & blues came to be in 1947, when Jerry Wexler, then a Billboard editor, began using it to denote the kind of postwar black pop that he went on to pioneer with Atlantic Records. Rhythm & blues became a chart name in the 25 June 1949 issue, replacing the previous issue's "Race Records".
Long before producing The Chris Rock Show and Good Hair, Nelson George was himself a Billboard reporter (he was behind the magazine's use of the term "black music"). But it was in the Village Voice that George came up with retro-nuevo, while reviewing Anita Baker in 1986. The term meant 80s black pop with roots in pre-disco R&B. "Black pop music had always felt grounded in a very adult perspective on life and love," George says. "The music became a lot more juvenile in the 80s. To me, 'retro-nuevo' was a way to highlight singers who were very contemporary but hadn't totally abandoned tradition."
George's longtime Voice editor was Robert Christgau, who made his own coinage with skronk, a phrase synonymous with no wave that Christgau first used in 1978. "It was a complete piece of onomatopoeia," Christgau says. "It just popped into my head. I was looking for a way to describe DNA and Mars. That's what the guitars sounded like to me."
Heavy metal was also first used to describe ugly guitars. The phrase, of course, originated with William S Burroughs in his 1962 novel The Soft Machine, featuring Uranian Willy, the Heavy Metal Kid. Then John Kay of Steppenwolf sang the phrase "heavy metal thunder" in 1968's Born to Be Wild. But it first reached print as a synonym for hard rock via Mike Saunders (later Metal Mike Saunders, singer for early-80s punks the Angry Samoans), in a review of Humble Pie's As Safe As Yesterday in Rolling Stone from 1970, describing the album as "more of the same 27th-rate heavy metal crap".
The same year, punk rock was coined Stone's Detroit rival, Creem, via Dave Marsh, who used it in a ? & the Mysterians live review ("Needless to say, it was impossible to pass up such a landmark explosion of punk rock, even after two nights running of Tina Turner"). Punk magazine came along a few years later.
Britain does nomenclature like no one else. Krautrock came from NME's Ian MacDonald in 1972, to describe Neu! and Can and the like; a year later, Faust led their album IV with the 12-minute epic Krautrock. Similarly, Simon Reynolds began using post-rock in early 1994 (he says he used it in Melody Maker, and the May 1994 issue of The Wire has his essay on it) to denote bands using rock instruments to non-rock ends. "I didn't actually coin it," says Reynolds, citing Richard Meltzer and Paul Morley's use of it before him as "an avant-rock synonym". He explains: "I made it into a concept."
Also in 1994, Andy Pemberton coined trip-hop in the June 1994 edition of Mixmag to describe the head-nodding instrumentals of DJ Shadow and the early Chemical Brothers. Similarly, dubstep first entered print in 2002, in sometime Guardian writer Dave Stelfox's XLR8R magazine feature on UK garage producers Horsepower Productions. According to the journalist Martin Clark, the term originally stems from a "tight circle" and originates either with UK promoter Ammunition or DJ Hatcha, whose Dubstep Allstars Vol 1 came out in June 2003.
As that indicates, the music business needs to know what it's selling and who it's selling to. Hillbilly music, a term that predates country music, was the coinage of Ralph Peer, who in 1925 recorded a North Carolina group he named the Hillbillies. When Peer recorded Jimmie Rodgers and the Carter Family two years later, the name stuck to the sound. Sire label boss Seymour Stein famously came up with new wave to sell punk to US audiences who were afraid of punk's violent connotations. In 1995, Motown executive Kedar Massenburg, who signed D'Angelo and Erykah Badu, came up with neo-soul as a way to sell them. (It definitively supplanted Nelson George's retro-nuevo.)
Bossa nova – Portuguese for "new wave" – gained currency, according to Brazilian music historian Ruy Castro, when it appeared in an advert for a 1958 multi-artist concert put on by Grupo Universitário Hebraico do Brasil. World music was hashed out in 1987 at an industry meeting. It was intended only for a brief marketing campaign to pump non-Anglophone musicians in retail spaces they might not otherwise fit into, only to remain an acknowledged, if unwieldy, category. Radio formats sometimes impose themselves on the music. AOR is a US abbreviation for "album-oriented radio" (later "rock") coined in 1972 by Lee Abrams and Kent Burkhart's consultancy firm for the FM rock radio stations that would define ultra-slick middle-American rock: Styx, Boston, Aerosmith. In practice, it usually translates to "definitively pre-punk".
And of course, radio plays a big role in the history of the term rock'n'roll itself – though it had been used in blues records dating back to 1922 (Trixie Smith's My Man Rocks Me with a Steady Roll, for example) and, as Preston Lauterbach's superb new book The Chitlin' Circuit makes clear, was basically everyday talk in postwar R&B: Roy Brown's 1947 Good Rockin' Tonight (later cut by Wynonie Harris and, on his second single, Elvis Presley); Wild Bill Moore's We're Gonna Rock, We're Gonna Roll (1947); the Dominoes' Sixty Minute Man (1950) ("I'll rock 'em, roll 'em all night long"). Then in 1952, Cleveland DJ Alan Freed switched his radio shows name from Record Rendezvous to The Moondog Rock'n'roll House Party.
A music genre is a conventional category that identifies some pieces of music as belonging to a shared tradition or set of conventions. It is to be distinguished from musical form and musical style, although in practice these terms are sometimes used interchangeably. Recently, academics have argued that categorizing music by genre is inaccurate and outdated.
Music can be divided into different genres in many different ways. The artistic nature of music means that these classifications are often subjective and controversial, and some genres may overlap. There are even varying academic definitions of the term genre itself. In his book Form in Tonal Music, Douglass M. Green distinguishes between genre and form. He lists madrigal, motet, canzona, ricercar, and dance as examples of genres from the Renaissance period. To further clarify the meaning of genre, Green writes, "Beethoven's Op. 61 and Mendelssohn's Op. 64 are identical in genre – both are violin concertos – but different in form. However, Mozart's Rondo for Piano, K. 511, and the Agnus Dei from his Mass, K. 317 are quite different in genre but happen to be similar in form."
Some, like Peter van der Merwe, treat the terms genre and style as the same, saying that genre should be defined as pieces of music that share a certain style or "basic musical language." Others, such as Allan F. Moore, state that genre and style are two separate terms, and that secondary characteristics such as subject matter can also differentiate between genres. A music genre or sub-genre may also be defined by the musical techniques, the style, the cultural context, and the content and spirit of the themes. Geographical origin is sometimes used to identify a music genre, though a single geographical category will often include a wide variety of sub-genres. Timothy Laurie argues that since the early 1980s, "genre has graduated from being a subset of popular music studies to being an almost ubiquitous framework for constituting and evaluating musical research objects".
Among the criteria often used to classify musical genres are the trichotomy of art, popular, and traditional musics.
Alternatively, music can be divided on three variables: arousal, valence, and depth. Arousal reflects the energy level of the music; valence reflects the scale from sad to happy emotions, and depth reflects the level of emotional depth in the music. These three variables help explain why many people who like similar songs from different traditionally segregated genres.
The earliest forms of music were probably drum-based, percussion instruments being the most readily available at the time (i.e. rocks, sticks). These simplest of simple instruments are thought to have been used in religious ceremonies as representations of animals. There was no notation or writing of this kind of "music" and its sounds can only be extrapolated from the music of (South) American Indians and African natives who still adhere to some of the ancient religious practices.
As for the more advanced instruments, their evolution was slow and steady. It is known that by 4000 BCE the Egyptians had created harps and flutes, and by 3500 BCE lyres and double-reeded clarinets had been developed.
In Denmark, by 2500 BCE an early form of the trumpet had been developed. This trumpet is what is now known as a "natural trumpet." It is valveless, and depends completely on manipulation of the lips to change pitch.
One of the most popular instruments today was created in 1500 BCE by the Hittites. I am talking about the guitar. This was a great step; the use of frets to change the pitch of a vibrating string would lead to later instruments such as the violin and harpsichord.
In 800 BCE the first recovered piece of recorded music was found. It was written in cuneiform and was a religious hymn. It should be noted that cuneiform is not a type of musical notation.
By 700 BCE there are records of songs that include vocals with instrumentals. This added a whole new dimension to music: accompaniment.
Greece was the root of all Classical art, so it's no coincidence that Classical music is rooted in Grecian innovations. In 600 BCE, famed mathematician Pythagorus dissected music as a science and developed the keystone of modern music: the octave scale. The importance of this event is obvious. Music was a passion of the Greeks. With their surplus of leisure time (thanks to slave labor) they were able to cultivate great artistic skills. Trumpet competitions were common spectator events in Greece by 400 BCE. It was in Greece that the first bricks in music theory's foundation were layed. Aristotle wrote on music theory scientifically, and brought about a method of notation in 350 BCE. The work of that genius is still studied today.
The next significant step in music's evolution was by Boethius. In 521 CE he brought the Greek system of notation to Western Europe, allowing the musicians there to scribe accurately the folk songs of their lands. Incidentally, it was Boethius who first wrote on the idea of the opera.
Most of the music created after Rome fell was commissioned by the church. The Catholic religion has a long history of involvement (for better or worse) with the musical arts. In 600 CE Pope Gregory had the Schola Cantarum built. This was the first music school in Europe.
Meanwhile in China, music was progressing also: it was reported that in 612 CE there were orchestras with hundreds of musicians performing for the assorted dynasties. Although the specific music from this period in China is unknown, the distinct style supposed to have developed there is reflected even in recent orchestral Asiatic pieces.
In 650 CE a new system of writing music was developed using "neumes" as a notation for groups of notes in music.
144 years after the Schola Cantarum was built, a singing school opened in the Monastery of Fuda, fueling the interest in musical vocation. And by 790 CE, there were splinters of the Schola Cantarum in Paris, Cologne and Metz. In 800 CE the great unifier Charlemagne had poems and psalms set to music. In 850 CE Catholic musicians had a breakthrough by inventing the church "modes." These modes would later metamorphose into today's major and minor scales. In 855 CE, the first polyphonic (2 unrelated melodies/voices at once) piece was recorded, and by 1056 this polyphonic style replaced Gregorian chants as the music of choice (even after the Church made polyphonic music "illegal"; this ban was later lifted). In 980 CE, the great tome Antiphononium Codex Montpellier was scribed.
In 1000 CE Guido D'Arezzo made many improvements in music theory. He first improved and reworked standard notation to be more user-friendly by adding time signatures. Then he invented solfege. This is the vocal note scale: do, re, mi, fa, so, la ,ti, do. This innovation has affected almost every modern vocalist.
In 1100 CE, a new secular movement began. This separation of Church from music was a straddling one, and soon this new "folk" music was looked down upon as pagan and borderline blasphemous.
On the dawn of the Renaissance in 1465 the printing press was first used to print music. By using a press a composer could organize his pieces and profit from them with great ease. In 1490 Boethius's writings on opera were republished in Italian.
With the onset of the Renaissance, the rules of music were about to change drastically. This was the beginning of a new enlightened age that would showcase some of the greatest musical minds ever produced.
The history of music at this point is best told by the styles that emerged and the composers who lived after the Renaissance.
As the year 1500 approached, choral music, the only kind of music that officially mattered at the time, experienced an eminence of development. Printing of music began in 1501 in Venice, commenced in Paris in 1528, and in England a few years later. Choral music highlight in the 1500s was the excitement by the discovery of a New World across the Atlantic, and the cultural competition brought on by the Protestant church movement. Event without these influences the change to a new century would have brought about new attitudes and plans. It would be a truly new and innovative time, and a highpoint would be reached through the medium of choral music.
Midway through the 1500s the Madrigal crystallized, resulting in yet more musical riches for decades to come. As the century continued individuals like Giovanni Pierluigi would create a treasure of choral riches that would stay in musicians' minds for centuries to come. Then almost systematically, the choral began abating around 1600. It was increasingly out of fashion. But, for the time being, Choral music was supreme.
Leading up to the 1600s the musical situation did not abruptly change, rather, there were a number of practices, some only seemingly new, that had begun, such as chordal writing with figured bass was rapidly catching on. Violin and keyboard lines were becoming more elaborate. There were troubles ahead, especially religious ones, but Music would endure and grow even amidst political and religious turmoil.
The Baroque period is characterized by strict musical forms and highly ornamental works. Baroque music began in Europe around 1600. It continued until 1750. For its time, Baroque was crazy and uninhibited. The music of this period is emotional and filled with little frills and decorations that shocked and amazed its listeners. Baroque was often fast paced with great and quick use of scales and violent changes in volume and melody. Today you might not think of it as an exciting type of music, but if you compare it to the Classical style you can tell immediately that baroque did have more action in its pieces. Some say the greatest composer of all time wrote in this period: Johann Bach.
The music of the Classical Period is lighter and clearer than Baroque music. In broad terms, it is less complex and is primarily homophonic. Ancient Greek art and culture had always been loved and emulated by European artists. This is especially evident in the Classical style (hence the name). The mathematical approach to music of Pythagorus and Aristotle took precedence in this period. It was the aim of Classical composers to achieve "perfect" music. That is, music that was completely perfect from a technical standpoint. This restriction led to very conservative music, strong but not really emotional. This is how most of Classical style music went and how the composers composed it (with the notable exception of Beethoven). Don't get the wrong idea about this; the music Mozart gave us is beautiful and moving, and he was a born and bred Classical composer. Conservative does not mean boring. There are many notable examples of the Classical style, including the musical stereotype that is Beethoven's 5th symphony.
Romantic music sought to express emotion, both negative and positive, through music. Orchestras became much larger during this period. This was a stark reversal of the Classical style of music; Romantic music was chock full of emotions and had no concern for Classical rules. It is said that Beethoven was almost singly responsible for the transition from Classical style to Romantic. Beethoven bridged the gap by infusing his later works with much emotion, and yet keeping within the Classical bounds. Soon the emotion overran the Classical bounds and Romanticism was born. There are many great composers of this era, including Carl Maria von Weber, Fredric Chopin, Hector Berlioz, and Johannes Brahms. Romantic music created two smaller movements in music: music about legends, and nationalistic music.
Storytelling was and is the prime directive of many musicians. Music has always been a medium for portraying legends and myths. In Romantic music this is no different. There have been many compositions telling the story of heroes (like King Arthur) and demons (especially Mephistopheles). This is just the logical outgrowth of the folk singers and wandering minstrels who had performed since the time of Beowulf. Wagner wrote many pieces on the basis of a story or myth. His famous "Ride of the Valkyries" is a great example.
Nationalism had been a growing craze after Napoleon's fall and Germany's unification, and this nationalism which led to World War I also led to some of the most inspiring music out there. Composers like Bedrich Smetana and Jan Sibelius wrote beautiful music to praise their homelands. In fact, Jan Sibelius is considered a national hero for the Finnish people. But if there was to be an epitome of nationalistic music it would be Peter Tchaikovsky, whose music about Russia defined a country's composing style for almost a century.
During the 20th century there was a vast increase in the variety of music that people had access to. Prior to the invention of mass market gramophone records (developed in 1892) and radio broadcasting (first commercially done ca. 1919–20), people mainly listened to music at live Classical music concerts or musical theater shows, which were too expensive for many lower-income people; on early phonograph players (a technology invented in 1877 which was not mass-marketed until the mid-1890s); or by individuals performing music or singing songs on an amateur basis at home, using sheet music, which required the ability to sing, play, and read music, which were skills that tended to be limited to middle-class and upper-class individuals. With the mass-market availability of gramophone records and radio broadcasts, listeners could purchase recordings of, or listen on radio to recordings or live broadcasts of a huge variety of songs and musical pieces. This enabled a much wider range of the population to listen to performances of Classical music symphonies and operas that they would not be able to hear live, either due to not being able to afford live-concert tickets or because such music was not performed in their region.
Sound recording was also a major influence on the development of popular music genres, because it enabled recordings of songs and bands to be inexpensively and widely distributed nationwide or even, for some artists, worldwide. The development of relatively inexpensive reproduction of music via a succession of formats including vinyl records, compact cassettes, compact discs (introduced in 1983) and, by the mid-1990s, digital audio recordings, and the transmission or broadcast of audio recordings of music performances on radio, of video recordings or live performances on television, and by the 1990s, of audio and video recordings via the Internet, using file sharing of digital audio recordings, gave individuals from a wide range of socioeconomic classes access to a diverse selection of high-quality music performances by artists from around the world. The introduction of multi-track recording in 1955 and the use of mixing had a major influence on pop and rock music, because it enabled record producers to mix and overdub many layers of instrument tracks and vocals, creating new sounds that would not be possible in a live performance. The development of sound recording and audio engineering technologies and the ability to edit these recordings gave rise to new sub-genres of classical music, including the Musique concrète (1949) and acousmatic (1955) schools of electronic composition. In the 1970s, African-American hip hop musicians began to use the record turntable as a musical instrument, creating rhythmic and percussive "scratching" effects by manipulating a vinyl record on the turntable.
The 20th-century orchestra was far more flexible than its predecessors and used a much wider variety of instruments. In Beethoven's and Felix Mendelssohn's time in the 19th century, the orchestra was composed of a fairly standard core of instruments which was very rarely modified. As time progressed, and as the Romantic period saw changes in accepted modification with composers such as Berlioz and Mahler, the 20th century saw that instrumentation could practically be hand-picked by the composer. Saxophones were used in some 20th-century orchestra scores such as Vaughan Williams' Symphonies No.6 and 9 and William Walton's Belshazzar's Feast, and many other works as a member of the orchestral ensemble. Twentieth-century orchestras generally include a string section, woodwinds, brass instruments, percussion, piano, celeste, harp(s), with other instruments called for occasionally, such as electric guitar and electric bass.
The 20th century saw dramatic innovations in musical forms and styles. Composers and songwriters explored new forms and sounds that challenged the previously accepted rules of music of earlier periods, such as the use of altered chords and extended chords in 1940s-era Bebop jazz. The development of powerful, loud guitar amplifiers and sound reinforcement systems in the 1960s and 1970s permitted bands to hold large concerts where even those with the least expensive tickets could hear the show. Composers and songwriters experimented with new musical styles, such as genre fusions (e.g., the late 1960s fusion of jazz and rock music to create jazz fusion). As well, composers and musicians used new electric, electronic, and digital instruments and musical devices. In the 1980s, some styles of music, such as electronic dance music genres such as house music were created largely with synthesizers and drum machines. Faster modes of transportation such as jet flight allowed musicians and fans to travel more widely to perform or hear shows, which increased the spread of musical styles.