Final answer:
Seinfeld was #1 in the Nielsen ratings from 1994 to 1998, marking the peak of its popularity.
Step-by-step explanation:
The television show Seinfeld was #1 in the Nielsen ratings during the years 1994-1998. This period coincides with the height of the show's popularity, as it received immense viewership and critical acclaim. Seinfeld is often regarded as one of the greatest and most influential sitcoms of all time.