Happy birthday to Terry Butler, the man known in the metal world as "Geezer." The bassist turns 63 on July 17. Geezer has been spending his summer playing dates on the 'Ozzy and Friends' tour, and, will be part of Black Sabbath's Lollapalooza set in early August.

Butler's low end really helped Sabbath's early metal favorites chug along, and 'N.I.B.' in particular was an essential track for many aspiring bassists. He left Black Sabbath in 1984, but never found the success with his Geezer Butler Band and G/Z/R solo projects. He did take part in several Black Sabbath reunions and was part of the Ronnie James Dio-led Heaven & Hell project in recent years.