The Composer’s Direction
A composer sometimes needs to instruct the performer how to properly interpret a composition so he uses certain directions to tell the performer how to play the piece. It could be just when and where to do something or merely how fast to play the song. Other times, the composer may not wish to repeat or rewrite a particular part as most compositions are repetitious. These directional or instructional symbols on the sheet music are an easy way for the composer to accomplish such tasks.
Directional Symbols Instructing the performer
Directional signs are merely instructions to the performer. With these symbols, the composer can tell the performer exactly how to interpret the composition and where to emphasize, repeat or separate specific areas. See also Ornamentation for some other marks of instruction to the performer.