Chart: (1) Any musical score. (2) A special type of score, used by Jazz musicians. Only the melody line, words (if any) and chord symbols are given. Clef, key signature and meter are given once only, at the beginning. The standards of musical notation and calligraphy are low. Details are often scanty or inaccurate, which encourages the musician to amend and elaborate the chart for his own purposes. Every Jazz musician has his own book of miscellaneous charts.
http://www.youtube.com/watch?v=2-BZfFakpzc