The book is primarily designed for introductory courses on "Stochastic Processes for Computer Science Students" in the third or fourth semester. It is also aimed at future or current computer scientists, engineers, mathematicians, and mathematics teachers who wish to acquire fundamental knowledge in stochastic modeling and gain initial insights into application areas. The book aims to enable readers to understand, model, and derive forecasts and decision-making aids for specific processes influenced by randomness in their essential aspects. Particularly tailored to the needs of computer science, it includes models and evaluations for operational problems and communication networks at a basic level. The concepts and methods are explained through numerous examples. The fourth edition contains additional notes on the mathematical aspects.