What are the key differences between a sonata, concerto, and symphony in classical music?

The key differences between a sonata, concerto, and symphony in Classical Music lie in their structure and performance. A sonata is a piece for a solo instrument or small group of instruments, typically in three or four movements. A concerto features a solo instrument accompanied by an orchestra, with a dialogue between the soloist and the orchestra. A symphony is a large-scale orchestral work, usually in four movements, showcasing the full orchestra without a soloist.