Dictatorship, is the political structure where a person or a single group of people of the same ideology has the absolut power. In this cases the three political powers ( legislative, Executive power, judicial ) are controlled by the same person or group.
Dictatorships can obtain power in different ways. Often they obtain the power after a coup d’etat but sometimes they are also elected or named by the single party.
In a dictatorship, the head of state and government is not change or maintain by secret, direct and free universal sufrage. In this cases, even when the dictator obtains the power through elections ( like Adolf Hitler), in a short period, the dictator forbide the other political parties and following elections, even some times there can be some manipulated pseudo elections for propagandistic reasons. In these elections, the dictator is the only elector candidate and the he/she obtains very high results.