What is it?
Copyright is the traditional form of licensing for intellectual property.
Why would I use it?
You've automatically got it with your work.
More info:
http://www.cipo.ic.gc.ca/eic/site/cipointernet-internetopic.nsf/eng/h_wr00003.html
What is it?
A flexible, simple, and standard set of licensing options. CC isn't an alternative to copyright; it's an addition to copyright that allows people to modify terms of copyright to best suit your needs and/or information ethics.
Why should I use it?
Creative Commons allows people to share, use, and build upon your work. You can do the same with other work licensed under CC. You can pick the terms of your license: available to use your work for profit or not, modify your work or not, or sharealike.
More info:
Full disclosure: Both Darby and Kathleen are big fans of Creative Commons. We feel that the traditional intellectual property system in Canada is a broken, outdated system, and that CC offers people a more flexible system of licensing that benefits everyone. We strongly advise eBook creators to use CC licensing, in whatever flavour you feel most comfortable with.
"Copyright is for Losers" by Jan Slangen: