Comparative politics is, as the name implies, the field of study in which scholars compare the political systems of various states. When scholars do this, they are trying to look at the major ways in which various states’ political systems are similar and different. By looking at these similarities and differences, they hope to understand how politics in general works across different contexts and they hope to understand how to improve any given state’s political system.
Comparative politics exists as a discipline because the world is a diverse place. There are hundreds of different states in the world, each with its own political system. There is no one way of running a political system that every state in the world agrees on. Instead of having a world where every state runs in the same way, we have a very diverse world.
Because we have diversity, we also have questions about what is best. The diversity of political systems in the world means that have many different ways that we could potentially choose to do things. We could, for example, have single-member legislative districts, proportional representation, or a combination thereof. As human beings, we naturally want to know which of these systems is best for us. This is where comparative politics comes into play.
Comparative politics looks at the different political systems of the world. It asks how they came to be different. It tries to understand how the differences in the political systems affect how well they work. For example, it might look at the different electoral systems mentioned in the previous paragraph and try to determine what effect each has on the types of political parties that arise in a given state. It might then look at what effect there is on a state when it has many small political parties as opposed to two or perhaps three major political parties. In other words, comparative politics looks at the differences between political systems and tries to understand why they exist and how/why they matter.
Comparative politics, then, is about the differences in political systems around the world. It examines the differences (and similarities) and tries to determine how they came about and how they affect the states in which they exist.