Discrete event simulation is a computer-based modeling technique used to study and analyze complex systems where events occur at specific points in time. It involves creating a virtual representation of a system, such as a manufacturing process or an airport operation, and then simulating the flow of events and activities over time. By incorporating key factors such as resource availability, processing times, and decision-making rules, discrete event simulation can help researchers and organizations optimize performance, improve efficiency, and make informed decisions about system design and operation. It is commonly used in various fields including manufacturing, healthcare, transportation, and logistics.