Software licenses stir up emotive feelings in the Linux community.
Proprietary software (often closed-source) imposes restrictions on what an end user can do with the application. The End User License Agreement (EULA) may prevent users from modifying the source code (or even the right to download it), copying or republishing the software. Some software developers (especially large corporations) regard proprietary software as being more beneficial to their business. For example, releasing the source code of their software may directly or indirectly aid their competitors. However, many Linux users regard proprietary software with disdain.
Organisations that produce Linux distributions also frequently take a dim view of closed-source software. For example, the Fedora Project encourages free and open source to the extent that no proprietary software can be included in Fedora. Although Ubuntu is also committed to free software, it adopts a more pragmatic position by making it easy for users to install non-free software.
Nevertheless, there's a surprising amount of free to download Linux proprietary software that is being used, especially graphics drivers (Nvidia, ATI), wireless firmware, MP3 Decoders, encrypted DVD support etc. However, the purpose of this article is to focus on more heavyweight applications.
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