Free software

From this simple definition flow many unexpected consequences. Today, free software is a large body of high-quality code on which much of the internet depends for critical functions, and it constitutes the core operating system for an increasing number of desktop machines as well. But free software is much more than just a collection of programs. It is also a political movement, a programming methodology, and a business model--although not necessarily to the same people at the same time. Indeed, even the term free software is controversial; as we'll see later, some people prefer to call it open source software. The story of how free software became so technologically successful, even as it became ideologically fractious, starts in the early days of the computer industry.