Jazz comes in a wide variety of styles, and has several defining features. The most important of these is improvisation. Jazz musicians do not follow a set piece of music note by note, but make up melodies and chord changes as they play. Such improvisation is based on a musician's creative impulses, and is often inspired by interactions with the other players or the audience. It is this energetic feedback and element of anticipation that gives jazz its incredible dynamism. A piece is never played the same way twice.

爵士乐以多种风格出现，具有几种可用作定义的特点。其中最重要的一种是即兴演出。爵士乐手不会按照固定的乐谱一个音符一个音符地演奏，而是在演出的时候自编旋律及变化和弦。这样的即兴演出基于乐手的创作冲动，通常是由与其它乐手或与观众间的互动激发起来的。正是这种充满活力的回应和充满期待的成分赋予了爵士乐不可思议的活力。一首乐曲绝不会有两次相同的演奏。

(短文节选,本篇始于：“爵”代风华 )