Everything you listen to nowadays with a guitar is thanks to blues, well except neo-classical stuff.
Rock N' Roll started off as a fusion of blues, RnB (the real rhythm n' blues), jazz and a bunch of others. In fact, if you play an old 50s rock n' roll beat slowly you'd swear it was blues. And to keep the story short, more bands and more drugs = rock n' roll branching off and ending up with what we have today.
