Complex sentence: When the show made its 1956 season premiere, it became one of the first color television programs; it was also the only NBC television show in the Nielsen ratings top ten for the 1956-1957 season.
Split into simpler sentences: When the show made its 1956 season premiere, it became one of the first color television programs. It was also the only NBC television show in the Nielsen ratings top ten for the 1956-1957 season.