Consider the question. That' 70s Show is an American television period sitcom that originally aired on Fox from August 23, 1998, to May 18, 2006. The series focused on the lives of a group of teenage friends living in fictional Point Place, Wisconsin from May 17, 1976 to December 31, 1979.

When did that 70's show first air?
If the answer is 'August 23 , 1998'; explain the reasoning:
To answer this question, we should know that: That' 70s Show is an American television period sitcom that originally aired on Fox from August 23, 1998, to May 18, 2006.