Lo-fi is the opposite of hi-fi.[1] Historically, the prescriptions of "lo-fi" have been relative to technological advances and the expectations of ordinary music listeners, causing the rhetoric and discourse surrounding the term to shift numerous times.[6] Usually spelled as "low-fi" before the 1990s, the term has existed since at least the 1950s, shortly after the acceptance of "high fidelity", and its definition evolved continuously between the 1970s and 2000s.