The 'Big Four' technology companies are four US multinational online service or computer and software companies that dominated cyberspace during the 2010s.

Apple Inc. was the first to be founded in 1976 by Steve Jobs, Steve Wozniak and Ronald Wayne. Apple Inc.'s initial business model was to develop and sell personal computers such as the Apple I, Apple II and later Macintosh models which were all highly successful. In the late 1990s when the company was struggling financially, Steve Jobs (who had left the company in 1985) rejoined and expanded the companies operations by launching the 'iMac' computer, opening the Apple Stores retail chain and broadening their software portfolio. Following this success, Apple Inc. shifted focus to consumer electronics such as the 'iPhone' which was launched in 2007.

Amazon was next to be founded in 1994 by Jeff Bezos. Originally conceived as an online marketplace for books, Amazon diversified its services to become the world's largest e-commerce marketplace.

Google was founded in 1998 by Larry Page and Sergey Brin while they were PhD students at Stanford University, California. To begin with Google started by hosting a new search engine but later moved into other areas such as online advertising and cloud computing.

Finally, Facebook was founded in 2004 by Mark Zuckerberg, Eduardo Saverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes. Facebook is the world's largest online social media and social networking service.

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