Probability theory and stochastic process theory are undoubtedly among the most important mathematic tools for the modern sciences. Probability theory has applications in several fields, such as biology, physics and the engineering sciences: population dynamics, signal and image processing, molecular chemistry,econometrics, actuarial science, financial mathematics, and risk analysis. This book provides an overview of stochastic models and methods for this very active field. Stochastic process theory is a natural extension of dynamic systems to random events. The book covers the modeling of random events in physics, biology, economics and the engineering sciences, while also introducing advanced problem-solving techniques in Bayesian statistics, signal processing and rare event analysis. No scientific background in stochastic process theory is needed.