Music
Music is an art form and cultural activity whose medium is sound organized in time. The common elements of music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics (loudness and softness), and the sonic qualities of timbre and texture (which are sometimes termed the "color" of a musical sound). Different styles or types of music may emphasize, de-emphasize or omit some of these elements. Music is performed with a vast range of instruments and vocal techniques ranging from singing to rapping; there are solely instrumental pieces, solely vocal pieces (such as songs without instrumental accompaniment) and pieces that combine singing and instruments. The word derives from Greek μουσική (mousike; "art of the Muses"). See glossary of musical terminology.
Opera
Opera (Italian: [ˈɔːpera]; English plural: operas; Italian plural: opere [ˈɔːpere]) is a form of theatre in which music has a leading role and the parts are taken by singers. Such a 'work' (the literal translation of 'opera') is typically a collaboration between a composer and a librettist and incorporates a number of the performing arts, such as acting, scenery, costumes and sometimes dance or ballet. The performance is typically given in an opera house, accompanied by an orchestra or smaller musical ensemble, which since the early 19th century has been led by a conductor.