Bo Diddley's influence on rock 'n' roll is well nigh immeasurable. Not only is his stage name synonymous with the cathartic drumbeat that accompanies a good portion of his music, he was also one of the first to incorporate the African-American street game "the Dozens" into the vocabulary of r'n'r imagery and posturing. This is before you even get to the primal, harmonic style of guitar playing he fathered, a style that matches Chuck Berry in scope of influence but arguably supercedes him in sonic invention. Where Berry's sound is rooted in the rolling of piano trills and flourishes, Bo Diddley's guitar comes from some mysterious place within himself. On such staples as "Mona" and "Bo Diddley," his guitar is dangerous, full of futuristic effects and natural distortion; vibrato and reverb test the levels on his recordings and he can sound like he's playing from the bottom of a crater on the moon. Often playing a single chord over and over with an imperceptibly mutating rhythm, Diddley lays the groove for his soaring, chorded leads that are as much a trademark as the jungle-fying drum and maraca combos that accompany. Everyone from Buddy Holly and the Stones to Johnny Thunders and, er the Dead have paid tribute to the master with covers, interpretations and outright swipes. Blues, R&B, Reggae and all-out rock 'n' roll songs pepper his massive catalog. While Bo Diddley's recent material shows his age a bit and may be for acolytes only, his material from the '50s on up to '70s is an essential to anyone interested in rock 'n' roll; not only as a cultural phenomenon but as a reason for living.