This lecture introduces the concept of computer simulations in cell biology, focusing on the types of simulations used, such as Molecular Dynamics and Monte Carlo. It explains the importance of simulations in gaining insights into complex biological systems, comparing them with experiments. The lecture covers the setup of simulations, including defining the system, specifying interactions, and choosing appropriate integration schemes. It also discusses the challenges and considerations in simulations, such as initial conditions, boundary conditions, and the accuracy of models. The lecture emphasizes the significance of quantifying errors in simulations and the limitations of modeling real systems. Overall, it provides a comprehensive overview of how simulations play a crucial role in understanding cellular dynamics.