Is piano part of every orchestra?

Answer:
Let's just say it's on the list as an instrument available for use in the orchestra. However, the piano is not used on every single piece of written music for the orchestra! The piano will be used only at the direction of the composer - it's the composer who specifies which instrument, and how many of each instruments, are used in his/her composition.
First answer by Bozidar. Last edit by Bozidar. Contributor trust: 1658 [recommend contributor recommended]. Question popularity: 1 [recommend question].