It is hard to imagine that a legal agreement can change an industry fundamentally. However, it is only a small exaggeration to say that the GNU Project’s General Public Licence (GPL) has reshaped the way that software is developed and sold. Seventeen years ago, the GPL helped launch the free software movement’s attack on proprietary software by using copyright law to make computer programs freely available to the general public.
Today, the GPL is the most widely-used open source software licence in the world and governs the use and distribution of the GNU Linux operating system, which runs software and hardware with an estimated value of $40bn (£22.8bn). Computer programs licensed under the GPL have become increasingly common among small businesses, as well as large corporate data centres.
