The Hershey's Bar is the most basic chocolate by Hershey's. It is a bar made of hardened chocolate. A fact that most do not know, the wrapper is actually a darker maroon color and not, in fact, a chocolate brown as the bar itself. Mini sized version. The candy and wrapper.
A sonata is a three movement piece of music, typically for one instrument with piano accompaniment, or just piano. Although they can be fore multiple instruments. Sonata form is a structure for a musical movement used not only in sonatas, but also in symphonies and concertos. The second movement of a sonata is usually a minuet or scherzo, and the third is commonly a rondo.
1 Some are in one movement; I know one symphony in 24 very short movements. Many composers have abandoned the usual forms altogether.  Variations on Sonata form in chamber music begin with Beethoven, who wrote some Piano Sonatas that are not really in Sonata form at all.