Original: Theodor Seuss Geisel ( ; March 2 , 1904 -- September 24 , 1991 ) was an American writer and cartoonist most widely known for his children 's books written under the pen name Dr. Seuss .
Simplified: Theodor Seuss Geisel ( ; March 2 , 1904 -- September 24 , 1991 ) was an American writer and cartoonist .