The post-war exploration of music, impelled by the LP, the transistor radio and the television, has taken Western music beyond early jazz into folk, rock and electronic music. Yet as old rules are questioned, man clings to the forms of music that will always remain rooted in the deepest instincts of his nature. Yehudi Menuhin examines the divergent trends in music following World War II: Bela Bartok's arrangements of traditional folk tunes; Oscar Peterson's jazz improvisations; John Cage's exploration of random sound; and the Beatles' impact as "pop idols" on an entire generation.