Concerto grosso means 'large concert' and it is 'a type of concerto in which a large group (known as the 'ripieno' or the 'concerto grosso') alternates with a smaller group (the 'concertino'), as Grove defines. This alternation between solo group and larger tutti gives a contrasting effect to tone color and more interesting variation of texture in a concerto grosso. In early Baroque, the concerto grosso form consisted of alternation of solo and ripieno sections, usually in slow – fast – slow – fast sections as shown in Corelli's examples. Later on, it began to use ritornello form which is a form where the opening theme returns several times in the first or final movement a solo concerto, concerto grosso or aria and it consists of fast – slow – fast sections (e.g. in Bach's concertos). In the ripieno section, string instruments are usually supported by a keyboard instrument and the concerto often had wood-wind. Most commonly, the concertino consists of two violins and cello as seen in the example of Corelli's op.6 and Handel's models.
At Corelli's time, instrumental ensembles were being transformed into sections and separated from voices and this has been developed into the concerto grosso. Many concerti grossi were composed under Corelli's influence in the early eighteenth century. 6 He was a very important figure in instrumental music and he standardized the concerto grosso form by setting up the basic format of the form, in which the concertino and ripieno relates to each other. Concerti grossi op.6 set was composed in 1716 and it represents a good example of conventional concerto grosso form. His works, in often cases, modulates to closely related keys (dominant or relative minor) and they often have walking bass and smooth voice leading, often moving by step, 4th and 5th. His Concerto grosso in F major op.6 no.2 was written for two Violins and cello or basso continuo for concertino and full orchestra for ripieno.