This document provides a timeline and overview of popular music genres and trends in the United States and United Kingdom from the 1940s to the 2010s. In the 1940s, blues and jazz were popular in the US while skiffle bands gained popularity in the UK. Rock and roll emerged as a dominant genre in the 1950s, particularly Elvis Presley in the US. The 1960s saw the rise of British beat groups like the Beatles and the growth of psychedelic rock. Hard rock bands like Led Zeppelin rose to prominence in the 1970s. New wave, hip hop, and new romanticism emerged in the 1980s. Grunge and Brit pop dominated the 1990s. Hip hop and teen pop were