He’s 63 today. According to the All Music Guide, Steve Cropper is:
Probably the best-known soul guitarist in the world, Cropper came to prominence in the early ’60s, first with the Mar-Keys (“Last Night”), then as a founding member of Booker T. & the MG’s. A major figure in the Southern soul movement of the ’60s, Cropper made his mark not only as a player and arranger (most notably on classic sides by Otis Redding, Sam & Dave, and Wilson Pickett) but as a songwriter as well, co-writing the classic “In the Midnight Hour.”
And Green Onions is the single greatest rock instrumental ever, period (Booker T. Jones, organ; Steve Cropper, guitar; Lewis Steinberg, bass; Al Jackson, drums). MG’s, by the way, stands for Memphis Group, not the car.
He also played with the Blues Brothers.