Women in rock describes the role of women singers, instrumentalists, record producers and other music professionals in rock music and popular music and the many subgenres and hybrid genres that have emerged from these genres. Women have a high prominence in many popular music styles as singers. However, professional women instrumentalists are uncommon in popular music, especially in rock genres such as heavy metal. "[P]laying in a band is largely a male homosocial activity, that is, learning to play in a band is largely a peer-based... experience, shaped by existing sex-segregated friendship networks.[1] As well, rock music "...is often defined as a form of male rebellion vis-à-vis female bedroom culture."[2]