When many people first hear about businesses that make their living selling open source software, their first question is usually something like “How can you sell something that’s available for free?” That complicated answer is addressed in this chapter.
Even restricting the discussion to “free as in beer” doesn’t simplify it much. The business world is full of examples of free and paid services or products supporting and subsidizing each other in various ways. While common, it can be a hard formula ...
