Democracy is a principle invented in Greece, that put simply states that all people of a given population regardless of social standing have an equal say in the authoritive decision making process. However, there is more than one type of democracy.
Representative (bourgeioise) democracy
This is the type of democracy usually adhered to in capitalist nations. Parliamentary democracy removes the actual descision making process from the public sphere and instead, each person is given a vote as to who they think should be the authoritive ruler. It is however a greatly flawed system under capitalism for several reasons. Firstly, the most rich and powerful power contestants generally have most access to the mass media which creates a biased pedestal in the sphere of public election debate. Secondly, since capitalist economies generally advocate small government and greater involvement by the private sector then governments are for the most part unnaccountable for the industries and services which generally effect voters lives anyway.
Direct democracy is the sort of democracy that communist or anarchist societies would strive to acheive. Instead of electing a given authoritive entity to make all other decisions on behalf of the people, each person has membership of the ruling body or government and is able to join in the descision making process on each individual issue. Direct democracy is classically termed "pure democracy".