In the online environment, content creation and protecting your work (and respecting the work of others) comes with a variety of pitfalls. Information placed online is not exempt to copyright concerns and, as such, many content creators will release their open source materials under some type of Creative Commons license.
For a brief overview of the types of Creative Commons licenses available, some of which protect the eTexts listed on this page, visit the Licenses and Examples page from creativecommons.org: