Back in the golden days if you were doing a research paper, most likely you would have to refer to an encyclopedia, as the internet wasn’t readily available as it is today.
As the internet got more popular we have seen Wikipedia gotten popularity over the encyclopedia. The information available from Wikipedia is crowd sourced and can be updated seconds after something happens, so readers are always up to date with information.
The accuracy of the information can be debatable that’s why colleges and universities do not allow Wikipedia to be used as a reference, however its appears to be the number one reference point for research papers and just about anyone in search on information.
PediaPress, the custom book publisher behind Wikipedia project recently started an Indiegogo campaign hoping that they can raise $50,000 in funding to publish a 1,000 volume print version of Wikipedia.
They want to publish 1,000 books in grey scale, but they might change to color if the funding goal is exceeded. New editions will have to be printed as new information becomes available though.