What is the difference between Silicon Valley and the San Francisco Bay Area? Is San Francisco a city or a county? Where in the Bay Area are the headquarters of the largest tech companies in the world?

This video explains the difference between San Francisco, Silicon Valley, and the Bay Area, gives brief overview of the history of Silicon Valley and how it came to dominate the tech industry, and gives you a tour of the Bay Area along with the companies headquartered there.

Image Credits:

Golden Gate Bridge: Rich Niewiroski Jr. - http://www.projectrich.com/gallery
Bay Bridge: Leonard G
San Francisco Skyline along Market Street from Twin Peaks: Vincent Bloch
San Francisco Street Map: Peter Fitzgerald, OpenStreetMap
Government Levels Responsibilities Sprites: Freeciv
Golden Gate Bridge driving away from SF: Weegee010
California Central Valley: LTSLTS
SV Family Tree/ Fairchildren graphic: IEEE Spectrum Magazine, October 2007
San Francisco Bay Area County Maps: Wikipedia Community
California Counties Map: Wikipedia Community
Map of North America: NuclearVacuum


Links for mobile users:

CGP Grey video which talks about Cities, Counties, and Incorporated vs Unincorporated places: https://www.youtube.com/watch?v=naDCCW5TSpU

Crash Course Government video on the separation of powers: https://www.youtube.com/watch?v=J0gosGXSgsI

Moore's Law: https://www.youtube.com/watch?v=rtI5wRyHpTg

Numberphile: https://www.youtube.com/user/numberphile

The difference between UK, GB, and England Explained: https://www.youtube.com/watch?v=rNu8XDBSn10

10 Funny Trolley Problems (On my other channel): https://www.youtube.com/watch?v=yywd3bXfYAg

Why is San Francisco so expensive?: https://www.youtube.com/watch?v=AAlA4hZ94OI

Mistakes:

Moore's first name is Gordon, not George
Lucasfilms moved to San Francisco in 2005, but much of the operation remains in Marin
Pronounciation