One of the most popular forms of music is known as jazz. Each year, hundreds of thousands of people attend jazz concerts and festivals in cities around the world. Jazz music, both old and new, is played on the radio and on home stereos. Two of the most important features of jazz music are "improvisation" and "syncopation." Improvisation means that music is created spontaneously by the musician during a performance. In other words, the musician modifies some existing music in a new and interesting way. Syncopation means that the regular patterns found in music may be broken up, with new accents and uneven patterns being created. The features of improvisation and syncopation are difficult to use with skill, and require great creativity on the part of the musician. Jazz music originated in the southern United States, during the late nineteenth and early twentieth centuries. It was based on African-American music that was derived in part from rhythms in western Africa. The earliest jazz musicians were influenced by a music style known as "ragtime," which was popular during the late nineteenth century. Jazz music also incorporated some aspects of a related kind of music called the "blues." By the beginning of the twentieth century, a fully developed form of jazz was being played in New Orleans, a city in the southern United States. Jazz musicians played instruments such as the trumpet, saxophone, cornet, and piano. Jazz soon became popular and was played on the riverboats that travelled along the Mississippi River. Some jazz musicians moved north to the city of Chicago, and young musicians in that city developed some new forms of jazz music. By the 1920s and 1930s, jazz was popular in many parts of the United States, and some musicians began forming large bands, comprising many musicians and many different instruments. This began the period known as the "big band" era when a popular form of jazz known as "swing" music was played. During the 1940s and 1950s, other forms of jazz, known as "bop" and "cool" jazz, were developed. Some people preferred these newer kinds of jazz, but others preferred the older varieties. By the 1960s, some jazz musicians began to experiment with different kinds of musical instruments and with other kinds of music. Some musicians incorporated musical styles from other parts of the world, or combined jazz with rock music, and today some musicians have blended jazz with rap music. However, some people prefer the more traditional forms of jazz music. Of course, most of the great jazz musicians of the early twentieth century-people such as Louis Armstrong, Duke Ellington, Count Basie, Dizzy Gillespie, and Billie Holliday-are no longer alive. However, many great jazz musicians are still active, and many younger musicians have continued this form of music. People will continue to enjoy jazz music for a long time to come.
