Behind so many great rock bands and rock songs looms the music of Chuck Berry.
Like the time a teenage Keith Richards ran into a childhood friend, Mick Jagger, at a train station in England and discovered they were musical soul mates.
"You know I was keen on Chuck Berry and I thought I was the only fan for miles," Richards wrote to a relative in April 1962. "I was holding one of Chuck's records when a guy I knew at primary school ... came up to me. He's got every Chuck Berry ever made and all his mates have, too."
Berry died Saturday at age 90, leaving behind not only a core of rock classics such as "Johnny B. Goode" and "Roll Over...