Where is the "Silicon Valley" in America?

San Francisco, also translated as "San Francisco" and "San Francisco", is a port city on the Pacific coast of California, USA. It is a world-famous tourist attraction and the fourth most populous city in California. San Francisco is close to Silicon Valley, a world-famous science and technology industrial zone. It is one of the important scientific research and development bases in the world and an important financial center on the west coast of the United States.