Stochastic processes are mathematical models that represent random phenomena evolving over time or space. These processes are used in various fields such as finance, engineering, biology, and physics to model uncertainty and variability in data. Stochastic processes can be discrete or continuous, and can be used to analyze the behavior of systems that exhibit randomness and unpredictability. The study of stochastic processes involves analyzing their properties, such as the probability of certain outcomes occurring, the expected values of variables, and the relationships between different variables within the process.