Ralf Grahn refers in his blog to the UK House of Commons Library Note: The European Union: a guide to terminology, procedures and sources (Standard Note SN/IA/3689; last updated 24 March 2010; 14 pages; authors Vaughne Miller and Emma Clark): http://www.parliament.uk/commons/lib/research/briefings/snia-03689.pdf
In addition to answering the questions, EC or EU law? Treaty of Rome or Treaty of Lisbon? First, Second or Third Pillar? Acquis Communautaire? Court of Justice or Court of Human Rights?, the Note clarifies some of the terminology used to describe the institutions, laws and procedures of the EU, and provides links to useful sources of information on the EU.