Avant-Garde Jazz differs from free jazz in that it has more structure in the ensembles (more of a "game plan") although the individual improvisations are generally just as free of conventional rules. Obviously there is a lot of overlap between free jazz and avant-garde jazz; most players in one idiom often play in the other "style" too. In the best avant-garde performances it is difficult to tell when compositions end and improvisations begin; the goal is to have the solos be an outgrowth of the arrangement. As with free jazz, the avant-garde came of age in the 1960s and has continued almost unnoticed as a menacing force in the jazz underground, scorned by the mainstream that it influences. Among its founders in the mid-to-late '50s were pianist Cecil Taylor, altoist Ornette Coleman and keyboardist-bandleader Sun Ra. John Coltrane became the avant-garde's most popular (and influential) figure, and from the mid-'60s on, the avant-garde innovators made a major impact on jazz, helping to push the music beyond bebop. — Scott Yanow

Free Funk is a mixture of avant-garde jazz with funky rhythms. When Ornette Coleman formed Prime Time in the early '70s, he had a "double quartet" (comprised of two guitars, two electric bassists, and two drummers, plus his alto) performing with freedom tonally but over eccentric funk rhythms. Three of Coleman's sidemen (guitarist James "Blood" Ulmer, bassist Jamaaladeen Tacuma, and drummer Ronald Shannon Jackson) have since led free funk groups of their own, and free funk has been a major influence on the music of the M-Base players, including altoists Steve Coleman and Greg Osby.

Free Funk is a mixture of avant-garde jazz with funky rhythms. When Ornette Coleman formed Prime Time in the early '70s, he had a "double quartet" (comprised of two guitars, two electric bassists, and two drummers, plus his alto) performing with freedom tonally but over eccentric funk rhythms. Three of Coleman's sidemen (guitarist James "Blood" Ulmer, bassist Jamaaladeen Tacuma, and drummer Ronald Shannon Jackson) have since led free funk groups of their own, and free funk has been a major influence on the music of the M-Base players, including altoists Steve Coleman and Greg Osby.

Third Stream (a term invented by composer Gunther Schuller in 1957) essentially means a mixture of jazz and classical music. Most attempts at fusing the two very different idioms have been (at best) mixed successes with string sections weighing down jazz soloists. In the 1920s, Paul Whiteman alternated between symphonic string sections and classic jazz solos. Strings were used in some swing bands in the 1940s (most inventively by Artie Shaw and Stan Kenton's dissonant works of 1950-51) but in all cases the added musicians were merely reading their parts and backing the improvisers. Starting with Charlie Parker in 1949, jazz players recorded now and then (while joined by strings), but it was not until the mid-to-late '50s that more serious experiments began to take place. Schuller, John Lewis, J.J. Johnson, and Bill Russo were some of the more significant composers attempting to bridge the gap between jazz and classical music. Most musical forecasters in the mid-'50s would have predicted that jazz's next phase would involve a fusion of sorts with classical music, but the rise of the avant garde (which has a spontaneity and an extrovertism that most pseudo-classical works lack) largely ended the third stream movement before it came close to catching on beyond academic circles. Since its heyday in the late '50s, there have been occasional third stream projects ranging from significant successes (such as Eddie Daniels' Breakthrough CD for GRP) to some that sound closer to pompous Muzak. Although the movement never really became a major force, it still has potential. — Scott Yanow

Short for "macro-basic array of structured extemporization," M-Base was developed by altoists Steve Coleman and Greg Osby, tenor saxophonist Gary Thomas, and various other young associates (including singer Cassandra Wilson) in the 1980s. An extension of Ornette Coleman's free funk (although with a greater use of space and dynamics), M-Base often features crowded and noisy ensembles, unpredictable funk rhythms, and an entirely new logic in soloing that owes little to bebop. Although the leaders of M-Base have since gone their separate ways (occasionally regrouping in different combinations), the influence of the music can be heard in the playing of some of the more adventurous young musicians. — Scott Yanow

Dixieland and swing stylists improvise melodically and bop, cool and hard bop players follow chord structures in their solos. Free Jazz was a radical departure from past styles for typically after playing a quick theme, the soloist does not have to follow any progression or structure and can go in any unpredictable direction. When Ornette Coleman largely introduced Free Jazz to New York audiences (although Cecil Taylor had preceded him with less publicity), many of the bop musicians and fans debated about whether what was being played would even qualify as music; the radicals had become conservatives in less than 15 years. Free Jazz, which overlaps with the avant-garde, remains a controversial and mostly underground style, influencing the modern mainstream while often being ignored.

Avant-garde Jazz differs from Free Jazz in that it has more structure in the ensembles (more of a "game plan") although the individual improvisations are generally just as free of conventional rules. In the best Avant-Garde performances it is difficult to tell when compositions end and improvisations begin; the goal is to have the solos be an outgrowth of the arrangement. As with Free Jazz, the Avant-Garde came of age in the 1960's and has continued almost unnoticed as a menacing force in the jazz underground, scorned by the mainstream that it influences. Among its founders in the mid-to-late 1950's were pianist Cecil Taylor, altoist Ornette Coleman and keyboardist-bandleader Sun Ra. John Coltrane became the avant-garde's most popular (and influential) figure and from the mid-1960's on the avant-garde innovators made a major impact on jazz, helping to push the music beyond bebop.