There’s a common misconception that open source software is free – as in doesn’t cost anything – and conversely that proprietary software is expensive.

I’d often wondered how this was aligned with the sale of packaged distributions of free software (it turns out I’m not the only one – a UK trading standards department were also confused by the sale of Firefox CDs – thanks to Slashdot via Slashdot Review for causing me to laugh out loud about that one…). Actually, it turns out that open source software is only free as in free speech – not as in free of charge. Sometimes it is free of charge too, but the two most common open source licensing models (GNU and BSD) do not prohibit the sale of “free software”.

GNU (a recursive name – GNU’s Not Unix) is a project, started by Richard Stallman in 1984 to create a free Unix clone, managed by the free software foundation (GNU/Linux is the kernel developed as a result of that project). GNU’s definition of free software says in part:

1. • The freedom to run the program, for any purpose (freedom 0).
   • The freedom to study how the program works, and adapt it to your needs (freedom 1). Access to the source code is a precondition for this.
   • The freedom to redistribute copies so you can help your neighbor (freedom 2).
   • The freedom to improve the program, and release your improvements to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this.

“Free software is a matter of the users’ freedom to run, copy, distribute, study, change and improve the software. More precisely, it refers to four kinds of freedom, for the users of the software:A program is free software if users have all of these freedoms. Thus, you should be free to redistribute copies, either with or without modifications, either gratis or charging a fee for distribution, to anyone anywhere…

…’free software’ does not mean ‘non-commercial’.”

The GNU general public license (GPL) encourages free software, but all enhancements and changes to GPL software must also be left as GPL. In effect, the software is free to enhance, but not necessarily free to purchase.

Where code is derived from the University of California at Berkeley BSD project, a separate licensing agreement applies. Many commercial software vendors prefer to use the BSD license, because it lets them wrap open source code up in a proprietary product. As Linux Format magazine paraphrased this month, “In a nutshell, the BSD licence says, ‘do what you like with the code – just don’t claim you wrote it'”. The BSD code would still be free, but the developers don’t have to release all of the source code for the entire product.

Whilst I’m writing about non-copyright licensing agreements, it’s worth mentioning creative commons. Not limited to software products, this is a licensing alternative to copyright for all creative works, building on the “all rights reserved” concept of traditional copyright to offer a voluntary “some rights reserved” approach.

I’m really interested in the rise of Linux as an alternative to Windows; however it’s not about stripping out software purchase costs. Purchasing a version of Linux with a predictable development cycle and a support entitlement (e.g. Red Hat Enterprise Linux or Novell/SUSE Linux Enterprise) can be just as (or even significantly more) expensive as a copy of Windows and management costs need to be considered too. For as long as the majority of IT organisations are geared up to provide almost exclusively Windows support, Linux support costs will be higher too.