Although GNU-Darwin can be viewed as a standalone OS for x86 and PowerPC architectures, it is also a source of free software to Apple users.The FreeBSD ports system was used to build over 15,000 software packages for Darwin and Mac OS X users. The ports system is a natural fit with Darwin and Mac OS X, because it orginates from the FreeBSD project. Standards compliance is very high in the ports system, which means that most of the packages build with little or no modification, and users get a familiar Unix-style installation. We GPL all of our original code, and most of the software which we distribute is GPL. We distribute an enhanced Darwin OS, and we provide a free software overlay which can be used by Darwin and Mac OS X users alike. It can also be used instead of Apple’s proprietary overlay, Mac OS X, if the users chooses that. GNU-Darwin has brought many thousands of free software titles to Darwin and Mac OS X, so that Apple users can experience the benefits of free software.
The article is at Kuro5hin.