Simulation principles Simulation is computational process. It involves the computations of simulated traffic dynamics, graphical animations and digital sound processing. As the simulator driver has the freedom to move as he or she likes, each moment new and unpredictable traffic situations will emerge in interaction with the simulated environmental participants. To cope with these unpredictable situations the simulated traffic is based on so called ‘autonomous agents’ technology, traffic participants who behave autonomously in reaction to the present situation without the need for predetermined or rigid control. These agents are software creatures who ‘live’ in their private world, the simulated environment, and who following their private set of behavioral rules. In this world, all activity is initiated and governed by means of scenario scripts which text-based instruction files to the simulator.