Many software products are released as so called OpenSource but how do the different kinds of OpenSource software licenses differ from each other?

For example Firefox is licensed under MPL/GPL and LGP. But what’s the Mozilla Foundation Licence? Often heart about that…

VLC media player makes it easy to me it’s just released under GPL which says something to me.

If you are the same way confused as me you might be interested in O’Reilly’s Openbook called “OpenSource & Free Software Licensing”

“This book will show you the licenses, explain how they can be used, and give you the information needed to make informed decisions. Knowing the details, the factual ones and not the FUD, will make you the ‘go to’ person when these type of questions arise.”
–Brian Turner, Free Software Magazine

Although a lot of questions I had got answered there are still serveral licences which are a mixture of others or explecit remoddeled.
A good example might be my beloved boost libraries which stand under a “Boost Software License”.

All links are to PDF documents:

• Chapter 1: Open Source Licensing, Contract, and Copyright Law

• Chapter 2: The MIT, BSD, Apache, and Academic Free Licenses

• Chapter 3: The GPL, LGPL, and Mozilla Licenses

• Chapter 4: Qt, Artistic, and Creative Commons Licenses

• Chapter 5: Non-Open Source Licenses

• Chapter 6: Legal Impacts of Open Source and Free Software Licensing

• Chapter 7: Software Development Using Open Source and Free Software Licenses

I hope it’s useful for your aims.