Conceptualizing Politics

General reference
There are two main reference works for philosophy in general online, which also 
contain entries regarding political philosophy, though our field is not their main 
focus:
1.  The Stanford Encyclopedia of Philosophy, available at http://plato.stanford.edu/
2.  The Internet Encyclopedia of Philosophy, available at www.iep.utm.edu/
As far as Wikipedia is concerned, it can and should be obviously widely used, pro-
vided the readers are able to distinguish well-carved and complete entries from 
those still in need of some or much additional work.
For a more analytical orientation tour in our field, two handbooks are useful:
Estlund, David (2012) The Oxford Handbook of Political Philosophy, Oxford: Oxford University 
Press.
Gaus, Gerald and Fred D’Agostino, eds. (2013) The Routledge Companion to Social and Political 
Philosophy, London: Routledge.
Whoever wishes to know more on a scholarly key about a number of categories, in