Excellent quick guide and overview to open source software compared to matching commercial software.
Open source: Literally “open source” means the source code is available to the users. One should not only get the source code but also have the right to use it. If the latter is denied the license is categorized as a shared source license.
Top 10 Open Source Applications:
- OpenOffice Draw
- Dia
- Gimpshop
- Paint.NET
- Partition Image
(Source) www.osalt.com