If it's got an acoustic guitar in, it's Folk. If it's got an electric guitar in and it's good, it's Indie. Otherwise if it's got an electric guitar in, it's Rock. If it's got no guitars, and you can't hear the synths for the drum machine, it's Dance. If it's got no guitars, and you can't hear the drum machine for the synths, it's Electronic. If it's got no guitars, and you can't hear the drum machine or the synths for the vocals, it's Rap. If it's got no guitars, drum machine, synths, or rapping, it's probably chamber music

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Peter