One way to extend a composition was, and is, to lay it out in several movements (or, to put it another way, join together several movements as a single composite work). A movement is a self-contained section of music that is part of a larger work; movements can be compared to chapters in a book. Movements in a multimovement work will always show some variety in tempo, meter, key, musical form, and mood.

The typical late Baroque concerto has three movements. The first movement is a bright, extroverted piece in a fast tempo. After this, the second movement strikes an obvious contrast: It is quieter, slower, and more emotional. The third movement is fast again — if anything, faster than the first.

In the first concerto we study, Vivaldi’s Violin Concerto in G, the three movements exploit two conventional forms of the Baroque era. The first and last movements are in ritornello form, the second movement in ground-bass form. To understand these forms and their contrast, we examine the first two movements.