A cappella [a kapˈpɛlla] (Italian for "in the manner of the chapel") music is specifically group or solo singing without instrumental accompaniment, or a piece intended to be performed in this way. It contrasts with cantata, which is accompanied singing. The term "a cappella" was originally intended to differentiate between Renaissance polyphony and Baroque concertato style. In the 19th century a renewed interest in Renaissance polyphony coupled with an ignorance of the fact that vocal parts were often doubled by instrumentalists led to the term coming to mean unaccompanied vocal music. The term is also used, albeit rarely, as a synonym for alla breve. 

A cappella music was originally used in religious music, especially church music as well as anasheed and zemirot. Gregorian chant is an example of a cappella singing, as is the majority of secular vocal music from the Renaissance. The madrigal, up until its development in the early Baroque into an instrumentally-accompanied form, is also usually in a cappella form. Jewish and Christian music were originally a cappella,[citation needed] and this practice has continued in both of these religions as well as in Islam.
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Jewish and Christian music were originally a cappella,[citation needed] and this practice has continued in both of these religions as well as in Islam.