Baroque music describes an era and a set of styles of European classical music which were in widespread use between approximately 1600 to 1750 (see Dates of classical music eras for a discussion of the problems inherent in defining the beginning and end points). This era is said to begin in music after the Renaissance and to be followed by the Classical music era. The original meaning of "baroque" is "irregularly shaped pearl", a strikingly fitting characterization of the architecture and design of this period; later, the name came to be applied also to its music. Baroque music forms a major portion of the classical music canon. It is widely performed, studied and listened to. It is associated with composers such as J.S. Bach, George Friedrich Händel, Antonio Vivaldi, and Claudio Monteverdi. During the period, music theory, diatonic tonality, and imitative counterpoint developed. More elaborate musical ornamentation, as well as changes in musical notation and advances in the way instruments were played also appeared. Baroque music would see an expansion in the size, range and complexity of performance, as well as the establishment of opera as a type of musical performance. Many musical terms and concepts from this era are still currently in use.
Music conventionally described as Baroque encompasses a wide range of styles from a wide geographic region, mostly in Europe, composed during a period of approximately 150 years. The term "Baroque", as applied to this period in music is a relatively recent development, first being used by Curt Sachs in 1919, and only acquiring currency in English in the 1940s. Indeed, as late as 1960 there was still considerable dispute in academic circles whether it was meaningful to lump together music as diverse as that of Jacopo Peri, Domenico Scarlatti and J.S. Bach with a single term; yet the term has become widely used and accepted for this broad range of music. It may be helpful to distinguish it from both the preceding (Renaissance) and following (Classical) periods of musical history. A small number of musicologists argue that it should be split in to Baroque and Mannerist periods to conform to the divisions that are sometimes applied in the visual arts.