Thanks to Red Hat for putting out a user-friendly video clip on the difference between BSD and GPL licenses:

In this video, Mark Webbink, Deputy General Counsel for Red Hat, delivers a broad
overview of the software licenses around open source, in layman’s terms.

The term "Free and Open Source Software," or FOSS for short, has come to
represent software that falls under one of two definitions: the Free Software
Definition of the Free Software Foundation, or the Open Source
Definition of the Open Source Institute. These licenses differ
slightly, but they agree fundamentally on three freedoms:

• The freedom to copy
• The freedom to make derivative works
• The freedom to redistribute

There are many open source licenses of various kinds, and all of them
agree absolutely on the nature of the first two freedoms. But the
third freedom—freedom to redistribute—is trickier. Two
prominent licenses, the GNU General
Public License (GPL) and the Berkeley
Software Distribution License (BSD) differ on this key point.
Mark explains the implications of these differences, and why they
matter.

Watch the video here.  Red Hat, unfortunately however, have managed to get bitten by GPL problems and the new White Box Linux phenomena.