Cleavage (politics)In political science and sociology, a cleavage is a historically determined social or cultural line which divides citizens within a society into groups with differing political interests, resulting in political conflict among these groups. Social or cultural cleavages thus become political cleavages once they get politicized as such. Cleavage theory accordingly argues that political cleavages predominantly determine a country's party system as well as the individual voting behavior of citizens, dividing them into voting blocs.
Dominant-party systemA dominant-party system, or one-party dominant system, is a political occurrence in which a single political party continuously dominates election results over running opposition groups or parties. Any ruling party staying in power for more than one consecutive term may be considered a dominant party (also referred to as a predominant or hegemonic party). Some dominant parties were called the natural governing party, given their length of time in power.
Two-party systemA two-party system is a political party system in which two major political parties consistently dominate the political landscape. At any point in time, one of the two parties typically holds a majority in the legislature and is usually referred to as the majority or governing party while the other is the minority or opposition party. Around the world, the term has different meanings.
Multi-party systemIn political science, a multi-party system is a political system in which multiple political parties across the political spectrum run for national elections, and all have the capacity to gain control of government offices, separately or in coalition. Apart from one-party-dominant and two-party systems, multi-party systems tend to be more common in parliamentary systems than presidential systems and far more common in countries that use proportional representation compared to countries that use first-past-the-post elections.