 This is the most common kind of written music used by professional session musicians playing jazz or other forms of popular music and is intended for the rhythm section (usually containing piano, guitar, bass and drums) to improvise their accompaniment and for any improvising soloists (e.g., saxophone players or trumpet players) to use as a reference point for their extemporized lines.A fake book is a collection of jazz songs and tunes with just the basic elements of the music provided.There are two types of fake books