<human>:  What is the difference between an orchestral piece and a symphony?
<bot>: The main difference between an orchestral piece and a symphony is that a symphony is typically a much larger work, with three or four movements, while an orchestral piece may have just one movement. A symphony also tends to include extended instrumental solos as well as complex sets of movements, while an orchestral piece may use a more basic set of motions. Additionally, a symphony usually features a full symphony orchestra, while an orchestral piece may feature a smaller ensemble. Additionally, a symphony often follows a set form, such as sonata or rondo, while orchestral pieces may be more loosely structured.