Direct and representative democracies are two types of democracies. They represent two types of governmental structures, while a presidential democracy is the third type that exists.
A democracy is defined as a type of government in which the citizens of the particular country have the right to participate in the decision-making process. In the presidential form of democracy, the president of the country is both the head of state and the head of government. In this form, the president is elected by the citizens.
A direct democracy is one in which the people govern directly. Known also as a pure democracy, the people vote on policies directly, rather than through any sort of parliamentary body. Switzerland is a country that follows a direct democratic system of government.
A representative democracy, also called an indirect democracy, differs from both the presidential and direct democracies because the people elect a representative body of individuals. Those individuals then are tasked with making decisions and voting on policies on behalf of the people. The head of state in a representative democracy is someone different than the head of government or the prime minister. The United Kingdom, with its governmental system that includes a queen as the head of state, is an example of a representative democracy.