Jazz

Jazz originated in the African-American communities of the Southern United States around the turn of the 20th century. Characterized by a unique mixture of influences, such as the tradition of New Orleans Brass Bands (itself fusing West African Music and European military Brass Band music), it was largely influenced by Ragtime and Blues, and quickly developed into one of the more popular musical genres by the 1930s with the development of Swing.

The general sound of jazz has changed many times over the past century, but one element that is present within most jazz is improvisation. Early blues was commonly structured around a repetitive call-and-response pattern; forms of Traditional Folk Music of the Black Americans in rural areas were also highly improvisational. Along with improvisation, blue notes and syncopated polyrhythms have also been recognized as features that are fundamental to jazz expression. Effectively, the genre has spawned its own vocabulary within music theory to describe its unique playing style, including concepts such as "swing" (a sense of rhythmic "feel" or "groove" created by musical interaction between performers) and the extensive use of the ii–V–I progression.

Among the earliest recognized styles were Dixieland, emerging in New Orleans in the 1910s, and Stride, an early form of piano music that evolved from ragtime. The Jazz Age ensued in the following two decades, and after having enjoyed nationwide popularity for the first time, the prominent sound began to shift from the dance-oriented Big Band Swing format to focusing on smaller groups that played the more rhythmically complex Bebop style, developed in the mid-40s.

The shift to bebop saw the focus placed on the virtuosic capabilities of single soloists, a characteristic that defined jazz at large in coming decades. In response to the energetic, 'fiery' style of the latter, Cool Jazz, a calmer and mellower playing technique, arose shortly afterwards. The controlled arrangements which borrowed from Classical Music aided in the advent of the further classical-influenced Third Stream approach. Soon Latin-infused styles appeared, such as Afro-Cuban Jazz, and later Samba-Jazz inspired by Brazilian Music; these would eventually contribute to the formation of the broader Latin Jazz movement. More experimentation followed, causing the emergence of Modal Jazz (which utilized musical modes instead of chord progressions as the basis of harmonic framework), and a decade later that of Free Jazz, which appeared in the dawn of what would become the more widespread Avant-Garde Jazz movement. In mid-60s, amidst the American civil rights movement, John Coltrane led the emergence of a style known as Spiritual Jazz, which incorporated influences from an eclectic range of religious and non-Western, notably Southeastern Asian, traditional music.

An era of fusion followed, specifically with other genres of African-American music, such as Jazz-Funk, the early incarnations of which shared similarities with the, by then established, sound of Soul Jazz. As the popularity of Rock music was becoming more prevalent in the 70s, practices such as Jazz-Rock and Jazz Fusion were born, combining the improvisational spirit and harmony of jazz with the electric instrumentation, amplified sound, and rhythmic vocabulary of rock music. The blend received a fair amount of criticism, and for many jazz purists, fusion was virtually incomprehensible as part of the accepted jazz tradition. Despite this, some of jazz's significant innovators, among them Miles Davis, crossed over from the Hard Bop scene into fusion, and later into the more commercial Smooth Jazz. By the 1990s, the mainstream popularity of Electronic music birthed what is known as Nu Jazz, a loosely defined genre that became a new avenue of exploration for jazz listeners.

Timeline of Jazz genres
A timeline of Jazz genres in order of peak popularity.

Dixieland - 1910s - 1920s

Avant-Garde Jazz - Mid-1950s - 1960s