What is epidemiology?

Epidemiology is the study of the distribution and determinants of health-related states or events in specific populations, and its application in the prevention and control of health problems.
The main object of study of epidemiology are the factors that determine the frequency and distribution of diseases in human communities.
The distribution of the disease refers to how the disease behaves in relation to time and place, and can be understood as a non-random form of disease distribution in a particular location.