Indie pop traces its roots back to post-punk fanzines and small independent record labels in London and Glasgow in the late 1970s and early 1980s. Its popularity grew with the publication of indie music charts in music magazines. A defining compilation cassette called C81 featured a wide range of emerging indie pop groups. Indie pop reflects the underground music scene's mellower side, with a greater emphasis on melodies, arrangements, and songwriting. It encompasses diverse styles from chamber pop to twee pop but focuses more on songcraft over sonic experimentation while still embracing the DIY ethos of punk rock.