Cupertino is a suburban city in Santa Clara County, California, U.S., on the western edge of the Santa Clara Valley with portions extending into the foothills of the Santa Cruz Mountains. The population was 50,546 at the time of the 2000 census.US Census 2000 Data for Cupertino, CAcensus.gov, Retrieved July 10,2007] The town has given its name to the Cupertino effect.