Silicon Valley

What Is Silicon Valley?

The term Silicon Valley refers to a region in the south San Francisco Bay Area. The name was first adopted in the early 1970s because of the region's association with the silicon transistor, which is used in all modern microprocessors. The area is notable for the vast number of technology companies that are headquartered there.

As such, Silicon Valley is a global hub for technological innovation, where hundreds of companies call it home. It is also known for being a center for innovation, entrepreneurial spirit, and a lifestyle founded on technologically based wealth.

Key Takeaways

  • Silicon Valley is a global center of technological innovation located in the South San Francisco Bay Area of California.
  • The area was named after the primary material found in computer microprocessors.
  • Silicon Valley is home to dozens of major technology, software, and internet companies.
  • Some of the major companies in the region include Apple, Alphabet's Google, Chevron, Meta, (formerly Facebook), and Visa.
  • It is one of the wealthiest regions in the world and one of the hottest real estate markets.

Click Play to Learn More About Silicon Valley

Understanding Silicon Valley

The term Silicon Valley was first used by Electronic News on its Jan. 11, 1971, cover. It was part of a three-part series written by journalist Don Hoefler, who was covering the history of the semiconductor. The term slowly expanded to include and be associated with technology, especially big tech.

Silicon Valley covers an area of 1,854 square miles and is home to more than three million people. It is located in the Bay region of California. Although its boundaries are somewhat nebulous, they generally include:

  • All of Santa Clara and San Mateo counties
  • The western edge of Alameda County
  • Scotts Valley in Santa Cruz County

The region's largest city is San Jose. It's also home to Stanford University and several state university campuses. This academic presence has helped fuel a rich research and development (R&D) synergy throughout the Valley.

The number of high-profile ventures born in Silicon Valley has made the region an attractive target for venture capital firms and investors. As many as 117 venture capital-backed initial public offerings (IPOs) in the area were valued at about $253 billion as of the beginning of December 2020. There were a total of 38 Fortune 500 companies located in Silicon Valley as of 2020, including:

  • Some of the most prominent tech companies, such as Apple, Alphabet's Google, Meta (formerly Facebook), and Netflix
  • Hardware and software companies like Cisco Systems, Intel, Oracle, and Nvidia
  • Giants in other fields, including Visa and Chevron

Special Considerations

The median household income in Silicon Valley surpassed those reported in San Francisco, California, and the United States. As of 2019, Silicon Valley households earned an average of $134,615 per year, while those in San Francisco and California earned $123,859 and $80,440. The national average totaled $65,712.

Silicon Valley is one of the wealthiest regions in the world. Forbes reported there were 365 tech billionaires across the globe with a combined net worth of $2.5 trillion. The 20 most affluent in this sector were worth $1.2 trillion combined. In 2018, 143 tech billionaires were reportedly living in Silicon Valley.

Several business leaders have recently decided to leave the region, taking their businesses to other parts of the United States or abroad. For instance, Tesla (TSLA) chief executive officer (CEO) Elon Musk announced the company was moving to Texas in December 2020. His announcement followed other major companies, such as Hewlett Packard (HPE) and Oracle (ORCL).

Business leaders leading the move out of Silicon Valley cited reasons like overall political climate in the region and looser COVID-19 restrictions in other parts of the country (compared to California).

A Brief Timeline of Key Silicon Valley Developments

  • 1939: William Hewlett and David Packard patent an audio oscillator, forming the foundation for the Hewlett-Packard company.
  • 1940s: William Shockley invents a silicon transistor at Bell Labs.
  • 1951: Fred Terman establishes Stanford Research Park as a partnership between Stanford University and the City of Palo Alto, providing a base of operations for both military and commercial technological innovations for companies such as Fairchild, Lockheed, and Xerox.
  • 1956: William Shockley opens his own firm, Shockley Semiconductor Labs, in Mountain View.
  • 1957: Several Shockley employees resign and start a competing firm, Fairchild Semiconductor. These men will later go on to start many other companies, including Intel and Nvidia.
  • 1958 to 1960: Robert Noyce and Jack Kilby independently discover that all parts of a circuit, including the transistor, can be created using silicon. Their discoveries led to the integrated circuit, created from silicon, used in all microprocessors today.
  • 1961: Former Fairchild backer Arthur Rock establishes Davis & Rock, considered the nation's first venture capital firm, giving rise to a new type of investment industry.
  • 1969: The Arpanet computer network is established with four nodes, including one at Stanford University. Arpanet is the foundation for the internet.
  • 1971 to 1972: Journalist Don Hoefler publishes a three-part report on the rise of technological development in the region in Electronic News, titled "Silicon Valley, U.S.A." He's credited with creating the region's name.
  • 1970s: Atari, Apple, Microsoft, and Oracle are founded.
  • 1980s: Cisco, Sun Microsystems, and Adobe are founded.
  • 1990s: Netscape, Google, Yahoo, Amazon, and PayPal are founded.
  • 2000 to 2010s: Meta, Twitter, Netflix, and Uber are founded.

Major Companies in Silicon Valley

Some of the major companies that call Silicon Valley home. Some of them include:

  • Apple (AAPL): Founded in 1976 by Steve Jobs, the company is based in Cupertino, Santa Clara County. The company's market capitalization is $2.41 trillion. It reported revenue of $274.15 billion in 2020. Apple's price-to-earnings ratio (P/E) was 29.14.
  • Alphabet (GOOG): The company's headquarters, which is often called The Googleplex, is located in Mountain View in Santa Clara County. It boasts a market cap of $1.88 trillion and a P/E ratio of 31.30. Alphabet reported full-year revenue of $182.35 billion in 2020.
  • Chevron (CVX): This multinational energy corporation calls San Ramon, Contra Costa County home. Chevron reported $94.40 billion in revenue in 2020 and has a market cap of $187.12 billion. Its P/E ratio is 52.25.
  • Meta (FB): One of the largest social media networks in the world, Meta is headquartered in Menlo Park in San Mateo County. The company has a market cap of $1.03 trillion and a P/E ratio of 27.62. Meta earned $85.96 billion in revenue in 2020.
  • Visa (V): Visa provides payment services and is headquartered in San Francisco. The company earned $21.85 billion in revenue in 2020. Its market cap is $471.62 billion and it has a P/E ratio of 46.63.
  • Wells Fargo (WFC): This financial services company was founded in 1852 and is based in San Francisco. The company earned $82.13 billion in revenue in 2020. It has a market cap of $190.82 billion and a P/E ratio of 13.30.

Where Is Silicon Valley in California?

Silicon Valley is located in the southern part of the San Francisco Bay Area of California. It encompasses more than 1,850 square miles in area.

What Is Silicon Valley Famous For?

Silicon Valley is known as a hub for technology companies, including Apple, Meta, Cisco, and other major companies like Visa and Chevron. The region attracts a great deal of venture capital and is home to some of the world's richest people.

Which Cities Are Part of Silicon Valley?

San Jose is the largest city in Silicon Valley. The region also includes Santa Clara, Redwood City, Mountain View, Palo Alto, Menlo Park, Cupertino, and Sunnyvale.

What Does Silicon Valley Unicorn Mean?

A Silicon Valley unicorn is the term given to a private startup in the region that is valued at over $1 billion. The term unicorn is commonly used in the venture capital industry. For instance, San Jose-based Zoom Video Communications (ZM) was valued at $1 billion in 2017. Founded in 2011, the company went public in 2019.

Article Sources

Investopedia requires writers to use primary sources to support their work. These include white papers, government data, original reporting, and interviews with industry experts. We also reference original research from other reputable publishers where appropriate. You can learn more about the standards we follow in producing accurate, unbiased content in our editorial policy.
  1. Pell Center. "WHY IS SILICON VALLEY CALLED SILICON VALLEY?" Accessed Sept. 20, 2021.

  2. Silicon Valley Indicators. "Snapshot of the Region." Accessed Sept. 20, 2021.

  3. Pitchbook. "Silicon Valley's banner year on Wall Street reshapes IPO landscape." Accessed Sept. 20, 2021.

  4. Fortune. "Fortune 500." Accessed Sept. 20, 2021.

  5. Silicon Valley Indicators. "Median Household Income." Accessed Sept. 20, 2021.

  6. Forbes. "Here Are The Richest Tech Billionaires in 2021." Accessed Sept. 20, 2021.

  7. Vox. "There are 143 tech billionaires around the world, and half of them live in Silicon Valley." Accessed Sept. 20, 2021.

  8. CNN. "Elon Musk is leaving Silicon Valley for Texas. These millionaires and companies are joining him." Accessed Sept. 20, 2021.

  9. HP. "A real gem: HP's audio oscillator patent turns 60." Accessed Sept. 20, 2021.

  10. San José State University. "The History of the Transistor." Accessed Sept. 20, 2021.

  11. Stanford Research Park. "PAST, PRESENT & FUTURE." Accessed Sept. 20, 2021.

  12. Computer History Museum. "FAIRCHILD SEMICONDUCTOR: THE 60TH ANNIVERSARY OF A SILICON VALLEY LEGEND." Accessed Sept. 20, 2021.

  13. PBS. "Integrated Circuits." Accessed Sept. 20, 2021.

  14. Harvard Business School. "Done Deals: Venture Capitalists Tell Their Story: Featured HBS Arthur Rock." Accessed Sept. 20, 2021.

  15. EDN. "ARPANET establishes 1st computer-to-computer link, October 29, 1969." Accessed Sept. 20, 2021.

  16. Tech Crunch. "Zoom, a profitable unicorn, files to go public." Accessed Sept. 20, 2021.