The Perl Toolchain Summit needs more sponsors. If your company depends on Perl, please support this very important event.
Each license name is hyperlinked to its location.
License
GPL v3.0
LGPL v3.0
BSD
MIT (X11)
Apache v2.0
Can You Release Commercial Works?
Yes, but ALL source code must be distributed under GPL (viral).
Yes
Yes
Yes
Yes
Can You Create Derivative Works?
Yes, but ALL source code must be distributed under GPL(viral).
Yes, but any derivative software must be released under a LGPL license and allow reverse engineering for client modifications and debugging.
Yes
Yes
Yes
Attribution?
Must be included in your source code and distribution.
Must be included in your source code and distribution.
Must be included in your source code and any documentation that you include with the release of your software.
Must be included with your source code.
Must be included with your source code, and you may be required to include it in your distribution if your licensor requires.
So What?
The GPL dominates the free software world by significant margins. While it’s a favorite for those committed to the open source movement, many are shying away from it because of its viral nature which can potentially scare clients.
Not viral like it’s GPL counterpart. Software can be dynamically linked to other LGPL licensed libraries without having to release your source code under LGPL. This license is generally used for software libraries with exception of programs such as Mozilla and Open Office. 
The BSD license is popular because of the flexibility it allows its licensees. There are really no limitations to what the licensee can do with the software other than the attribution requirements.
This is becoming a very popular license because of the extreme simplicity of its text. The whole license is about half a page long and is very permissive like the BSD license.
This license is somewhat similar to the BSD license, but goes into further detail in the attribution clauses and maintenance of intellectual property rights. Choosing this license over the BSD or MIT license is a matter of how specific you want your protections to be.