Have you ever read a physical, published, academic journal? Chances are, if you have, it was probably at a centralised institution like a library or university.

But there are digital versions available online, right?

Absolutely, and the Internet has done a great job of improving the reach of scientific research.

But these online resources are still highly centralised. Most access is controlled by universities (again) and publishers. Access is usually restricted to those with money and/or the correct affiliations.

In addition, there are unknown quantities of research being done behind closed doors, by governments and corporations. Little to no access is available for the public to this research.