Indie rock originated in the mid-1980s to describe bands that existed outside of the mainstream and on independent record labels. It is a sub-genre of alternative rock that has produced many other sub-genres over time, from grunge to post-punk revival. While initially used to refer to non-commercial bands, the term is now ambiguous because some indie rock bands like Coldplay, Arctic Monkeys, and Oasis achieved commercial success in the 1990s and 2000s. The genre represents a diverse range of musical styles.