A musical composition for a solo instrument is called a "sonata." Sonatas typically consist of multiple movements, each with varying tempos and moods. Common instruments for sonatas include piano, violin, and flute, allowing composers to showcase the instrument's range and expressive capabilities. In Western classical music, the sonata form has been a popular structure since the late Baroque period, evolving through classical and romantic eras. Renowned composers like Ludwig van Beethoven and Franz Joseph Haydn contributed significantly to the sonata repertoire, creating works that remain staples in the concert repertoire today.