I will review the field of numerical simulations of cosmic reionization:
the process of ionizing of intergalactic medium by high redshift
galaxies and quasars. I will describe the main physical processes that
are important for modeling reionization, explain how these processes are
incorporated in computer simulations, and will use simulations to gain
insight into the actual reionization process. I will finish with an
illustration of how the exponential progress in computer industry allows
us to solve problems that we could not even dream about mere 10 years ago.