WLCG, the Worldwide LHC Computing Grid

Who can use WLCG is explained on the collaboration wwebsite at https://wlcg.web.cern.ch/using-wlcg/

EGI grid overview

EGI general description is available at https://www.egi.eu/about.

Grid documentation

Here is a very useful document if you don't know anything about the Grid: https://forge.in2p3.fr/attachments/download/13593/La_Grille_pour_les_Nuls_v1.0.pdf

Grid training

A Massive Open Online Course (MOOC) on Grid Computing is available at http://doc.grid.surfsara.nl/en/latest/Pages/Tutorials/MOOC/mooc.html#mooc