HOWTO: Pick an open source license

This article is about how to choose an open source license.
It can be boiled down to this decisiontree, but check the link to see examples.

How should I choose an open source license?

Do you want to release any control over how your code is used and distributed?

• YES: Don't copyright it. Put it in the public domain, and you're done.


• NO: Copyright the code (paste copyright notices all over it)
  
  Do you want to allow people to use your code in non open-source programs?
  
  • NO: Release your code under the GPL licence
  
  
  • YES: If somebody uses your code in their program and sells their program for money, do you want some of that money?
    
    • YES: Two choices:
      
      1. Don't release it as open source
      
      
      2. Dual license
    
    
    • NO: "Commercial friendly" license
      
      If somebody uses your code and improves it (fixes bugs or adds features) do you want to make them give you the improvements back so you can use them too?
      
      • YES: Use a "reciprocal" license.
      
      
      • NO: Use a "non-reciprocal" license.
      
      

See:
HOWTO: Pick an open source license (part 1) | Ed Burnette's Dev Connection | ZDNet.com
http://www.opensource.org/licenses