Big Four tech companies
The Big Four are four tech companies described by Eric Schmidt, Phil Simon, and Scott Galloway as driving a large amount of growth in technology. The Four companies are Alphabet Inc., Apple Inc., Facebook, and Amazon. The Big Four are sometimes referred to as GAFA, an acronym for Google, Apple, Facebook, and Amazon.
The term refers to companies driving large societal change, rather than just the largest tech companies. Schmidt, Simon, and Galloway consider some large companies such as IBM and Microsoft to be driving less change than the Big Four. 
- "Eric Schmidt's Gang Of Four: Google, Microsoft, Amazon, And Facebook – TechCrunch". techcrunch.com.
- Pisani, Bob (3 October 2017). "We are letting Amazon and Apple 'avoid taxes, invade privacy, and destroy jobs,' says NYU professor". CNBC.
- "GAFA Approach to Digital Banking Transformation - Accenture". www.accenture.com.
- Simon, Phil (October 22, 2011). The Age of the Platform: How Amazon, Apple, Facebook, and Google Have Redefined Business (1 ed.). Motion Publishing. p. 312. ISBN 9780982930250.
- Galloway. The Four: The Hidden DNA of Amazon, Apple, Facebook, and Google. ISBN 0525501223.