to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
From an image by why the lucky stiff. The full image is found [http://www.poignantguide.net/ruby/chapter-7.html here], as part of ''Why's (poignant) Guide to Ruby''. The book is under the Attribution-ShareAlike 2.5 license, as indicated on the "