Formally, Benjamin Grimm, but you'd best call him Ben.
Best friend of Reed Richards. Grimm was exposed to cosmic rays on a space flight with Richards, along with Richards' fiance Sue Storm, and her brother Johnny.
This exposure mutated Grimm into a pile of super strong sentient orange rock, a transformation that couldn't be reversed. He called himself The Thing. His co-astronauts also each received a strange superpower as a result of the cosmic rays, and together the quartet banded together to fight evil as The Fantastic Four.
Grimm is fond of cigars, and often likes to tell his enemies (including the Incredible Hulk) "It's CLOBBERIN' time!!!!"
The Fantastic Four and all characters named herein were created by Stan Lee, Jack Kirby, and Marvel Comics.