Introduction (music)
Template:Short description In music, the introduction is a passage or section which opens a movement or a separate piece, preceding the theme or lyrics. In popular music, this is often known as the song intro or just the intro. The introduction establishes melodic, harmonic or rhythmic material related to the main body of a piece.<ref name="Pease">Pease, Ted (2003), p.172. Jazz Composition : Theory and Practice. Template:ISBN.</ref>
Introductions may consist of an ostinato that is used in the following music, an important chord or progression that establishes the tonality and groove for the following music, or they may be important but disguised or out-of-context motivic or thematic material.<ref name="Pease"/> As such, the introduction may be the first statement of primary or other important material, may be related to but different from the primary or other important material, or may bear little relation to any other material.
A common introduction to a rubato ballad is a dominant seventh chord with fermata,<ref>Weir, Michele (2005). Jazz singer's handbook: the artistry and mastery of singing jazz, p.53. Alfred Music. Template:ISBN.</ref> {{#if:Blues intros - dominant seventh fermata.mid|{{#ifexist:Media:Blues intros - dominant seventh fermata.mid|<phonos file="Blues intros - dominant seventh fermata.mid">Play</phonos>|{{errorTemplate:Main other|Audio file "Blues intros - dominant seventh fermata.mid" not found}}Template:Category handler}}}} an introduction that works for many songs is the last four or eight measures of the song,<ref>Weir (2005), p.57.</ref> {{#if:Blues intros - last four measures.mid|{{#ifexist:Media:Blues intros - last four measures.mid|<phonos file="Blues intros - last four measures.mid">Play</phonos>|{{errorTemplate:Main other|Audio file "Blues intros - last four measures.mid" not found}}Template:Category handler}}}} while a common introduction to the twelve-bar blues is a single chorus.<ref>Weir (2005), p.55.</ref> {{#if:Blues intros - single chorus.mid|{{#ifexist:Media:Blues intros - single chorus.mid|<phonos file="Blues intros - single chorus.mid">Play</phonos>|{{errorTemplate:Main other|Audio file "Blues intros - single chorus.mid" not found}}Template:Category handler}}}}
If a movement in sonata form form begins with an introductory section, this introduction is typically not considered part of the movement's exposition.