Articles written on Gamedev.net can be published under a number of different licensing options. The purpose of these licenses is to give a certain measure of protection to the author as well as anyone who may use the content of the article (or included code). When I was younger I was very much in the camp that if I were to give something out I would just put it out there into the public domain. Unfortunately there are a slew of legal complications that can arise out of someone using source that you write. There are at least some minimum protections that you need to have as an author. For example, most open source licenses will get you off the hook if the code you write ends up violating a patent and someone using it is sued for that patent violation.
This is the license we prefer that all members use for publication. In a nutshell we developed this license to treat the article a little different from any attached code. This is not a viral license. As an author you get a lot of the protections you would see in licenses like MIT/Z-Lib such as limitation of liability and a warranty disclaimer. The article itself cannot be freely reproduced without your permission. Any source code that is included with the article or attached can be freely used in commercial products without a need to attribute you for the work (although it is recommended).
Very liberal. Basically, you can do whatever you want as long as you include the original copyright.
This is not technically a license. You release all rights to both the article and the code. As a careful note of consideration there are some technical pitfalls to releasing a work into the public domain. One such pitfall is that in some nationalities it may not actually be legal to release a work entirely. Therefore all the protections granted to you by other licenses will not be in effect.
This license is used for the zlib library and some other open-source libraries/packages. It is very short and very permissive. It requires you to change the name of modified software and contains a sentence removing liability from the authors of the software.