Vivaldi cast "The Four Seasons" in the form of four concertos for solo violin and string orchestra. Concertos are designed to feature an instrument which not only enjoys an especially prominent role but plays technically brilliant, or virtuosic, passages. In addition to juxtaposing the sound of the solo violin to the full ensemble, Vivaldi occasionally added a few instruments with the solo violin to create the musical textures of chamber music. Each of the concertos that comprise "The Four Seasons" follows a three-movement plan that Vivaldi helped to establish as the standard concerto form.