Silicon Valley is home of 40 different cities in the southern San Francisco bay area. It is called Silicon Valley because of the silicon that is found their, and is the home of the semiconductor chip industry in the world. It has been called Silicon Valley ever since January 11,1971.  The thing that makes Silicon Valley so important is the revolution that changed in technology, and the discoveries they had found there. Bill Gates build his first computer in Silicon Valley.
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By: Jeremy Vandever