This is an informal summary of important properties of the GNU GPL in a form, which is hopefully easy to read and understand. This text however does not replace the lecture of the original license-text. There is explicitly no warranty for mistakes, misinterpretation, imprecise explanations, faulty translations or errors. Note that this text may be subject to change at any time.

• Obligation to name the author
  You HAVE TO keep intact any notices that name the author, copyright notices, notices of the absence of any warranty and the license of the software. Please accept: Only the author decides how often and in which form these notices are appear in the software - not the user.
• Right to distribute freely
  You MAY share the complete software with others for free, even through P2P networks. Each copy must contain a copy of the license text and the complete, not shortened, unencrypted source code.
• Right to adapt and extend
  You MAY create adaptions and extensions of the software, as long as you comply with all obligations of the license (e.g. keeping intact copyright notices). You have the obligation to clearly mark any changes that you have made to the source code. Any adaption or extension you make is to be licensed under the terms of the GNU GPL and becomes open source software as well.
• Right to use the software for commercial purposes
  You may use the software even for commercial purposes without paying a license fee. You may also provide extensions or adaptions for yourself or a third party and get paid for your work. BUT: You MAY NOT, charge any fees for using the software - not even for your own applications, if the build upon or use this software.

License text

• GNU GPL v3 - license text (Englisch)
• GNU GPL v3 - german translation
• Free Software Foundation Homepage (Englisch)