Popular opinion about open-source software – having access to the source code – does not adequately express the meaning of free software; it is even weaker than official definition of open-source as it includes lots of propriety and/or commercial programs.

Free software does not imply that software is available at zero cost; it is possible to pay money to buy open-source software; however you are FREE to modify and change it and even possibly sell copies! A free program must be available for commercial use, development and distribution. Strange? Think Red Hat Linux, Red Hat Linux is open-source software but not freeware.

Freeware expresses the concept of not charging for use; this is the meaning of “free as in free beer”; freeware however does not guarantee access to the source code . By not using open standards, it is easy to lock in users (who might be attracted by the zero cost) and prevent them from moving on to other software later.

On the other hand, “free as in free speech” means you get access to the source code and can change it as you will. According to Richard Stallman of FSF and GNU fame,  free software can be used, studied, distributed, changed, copied and improved by users. Fortunately, most open-source software are freeware. Users of open-source software don’t have to worry about what happens if their software gets bought out; it also assures of some form of updates as anyone can improve the software.

Here are some of the most widely-used licenses

• General Public License (GPL) – Anyone who obtains software licensed with the GPL has the right to get the source code along with the software, create anything they like and redistribute it under the same GPL.
• Mozilla Public License – This gives users the right to modify your software. However ,they have to release all your files with their software but do not have to release the files they created from the scratch.
• Lesser General Public License (LGPL) – Similar to the GPL, but gives people the flexibility to use open-source software in their own projects without releasing all the source code to the world.
• Apache 2.0 License – Users can use the source code as they will provided they include the copy of the license in their distributions and use the proper attributions.
• BSD License – A very open license, allowing users to do practically anything with the software. All you have to do is include the copyright, conditions and disclaimer; also you can’t use the name of the originating organization to promote your edit without written consent.

• MIT License – This is similar to the BSD License, but even more permissive.
• Public Domain – This is completely permissive; anyone can do anything they like with these software as there is no copyright. SQLite is a popular example of public domain software.

Next time you get free software, find out what kind of ‘free’ it is!