One part of California is Silicon Valley.
San Jose ( [ ˌsæn_hoʊˈzeɪ ] , Spanish for `` Saint Joseph '' ; [ saŋ xoˈse ] ) , officially the City of San José , is the economic , cultural , and political center of Silicon Valley and the largest city in Northern California . The Santa Clara Valley runs south-southeast from the southern end of San Francisco Bay in Northern California in the United States . Silicon Valley is a nickname for the southern portion of the San Francisco Bay Area , in the northern part of the U.S. state of California . The `` valley '' in its name refers to the Santa Clara Valley in Santa Clara County , which includes the city of San Jose and surrounding cities and towns , where the region has been traditionally centered . As more high-tech companies were established across the Santa Clara Valley , and then north towards the Bay Area 's two other major cities , San Francisco and Oakland , the `` Silicon Valley '' name eventually came to refer to all high-tech businesses in the region .