Always wonder what is the difference between the GPL, the Ms-PL, Creative Commons, and the MIT software licenses are? Over at the Code Project, they have a extremely easy to understand breakdown of software licenses.
- Provides copyright protection
- Can be used in commercial applications
- Bug fixes / extensions must be released to the public domain
- Provides an explicit patent license
- Can be used in closed source applications
- Is a viral licence
In addition, Wikipedia has another great listing of software licenses.