a region in Northern California along the west shore of the San Francisco Bay, that stretches from San Jose to San Francisco, that is a major center for high-tech manufacturing and numerous web-based corporations. It has a high cost of living as a result and and is among the most expenesive regions in the United States to live.
Silicon Valley is an informal term for the Santa Clara County region in California. The county is home to several headquarters of major tech, software, and social media business giants in the vicinity. It employs an immense amount of people and brings in lots of revenue to the area. There are alot of educated young people (computer scientists, tech engineers, software developers) who live there for work.