[en] Fuel cells represent one of today's most promising non-polluting technologies for power applications. Extensive research has targeted the modeling of the mobile ion dynamics through electrolytes, which are an essential component of the fuel cells. For the fuel cells operating at low temperatures, the polymer electrolyte membranes (PEMs) have shown attractive characteristics as very good proton conductors under specific operating conditions. However, fundamental processes such as diffusion mechanisms through the membranes are still insufficiently understood, and many experimental and theoretical investigations are currently in progress. This paper focuses on the simulation of proton transport through water and PEMs using a range of molecular dynamics and Monte Carlo techniques. The mechanisms assumed for the diffusion processes are discussed. Some new computer programs that aid in visualization of the transport of protons are described. Results of the computer simulations are presented in terms of diffusion coefficients and are compared with available experimental data. The programs will eventually permit investigations of various membrane structures and the role of different dopants (e.g., diamond dopants). (author)