An ideology is a collection of ideas. Typically, each ideology contains certain ideas on what it considers to be the best form of government (e.g. democracy, theocracy, etc.), and the best economic system (e.g. capitalism, socialism, etc.). Sometimes the same word is used to identify both an ideology and one of its main ideas. For instance, "socialism" may refer to an economic system, or it may refer to an ideology which supports that economic system.