Your freedom matters: all our learning material is free, like in Wikipedia; we mean both 'free' as in 'freedom' and 'free' as in 'free lunch'.
You can use it for whatever you like under the terms specified in Creative Commons Attribution-ShareAlike License. By Attribution we mean that you must attach a note that you got the data you use from bubrary.net and name the data's authors (or link to them if naming them is practical, e.g. work is not mainly collective). See details in help.
Alpha Testing: there are known bugs and some functionality is not yet available