System testing is basically a part of software testing and test plan should always contain specific space for this testing. To test the system as a whole, requirements and expectations should be clear and the tester needs to understand real time usage of application too.
The city of Milwaukee, Wisconsin was chosen as the location in which Happy Days was set. Tom Miller, one of the producers, grew up in Milwaukee. In addition, Milwaukee gave the show a midwest flavor that they thought would appeal to a broad-based audience.
Following these changes, Happy Days became the number-one program in television in 1976-1977, Fonzie became one of the most merchandised characters of the 1970s, and Henry Winkler became a major star. The series also spawned a number of spin-offs, including the hit shows Laverne & Shirley and Mork & Mindy.