The set of licences that are creative commons allow for copying and distribution of the works, as long as some restrictions are met. These restrictions are represented by two-letter abbreviations, that are added to CC, for example CC-BY-SA (the license Wikipedia uses).
The meaning of the abbreviations are:
- BY: Attribution - Credit the creator(s)
- NC: Non commercial - it isn't permitted to use the work commercially
- ND: Non derivate - it isn't permitted to change the work
- SA: Share alike - it is permitted to change the work as long as the derivate is distributed under the same license
Read more about it on their website.
So, the CC-BY-SA of Wikipedia means you can print a book of articles, as long as you credit the authors and distribute the contents of the books under the same license CC-BY-SA. As some books containing content of the Wikipedia already do.
The NC-clause would disallow you to ask for money for distribution the book (luckily not the case for Wikipedia). The ND-clause would disallow to change the content, obviously not the right choice for Wikipedia, as an article wouldn't be allowed to be changed from someone different than the original author.
Every CC-license allows to copy, if it is non-commercial, unchanged and credits the author.