Several VisualBots methods such as TurnRand and ColorRand make use of an internal random number generator to impart a degree of randomness to simulations. You can also assign random numbers drawn from statistical distributions to VisualBots properties using the Random object. The Random object exposes a number of statistical distributions such as with the Real, Whole, NormDist, and TriDist methods.
Random behaviors and numbers generated by the above methods are not random in the strictest sense - they result from iterating a formula over and over again, using the last random number as an input seed to generate the next. The resulting sequence of numbers can be reproduced by knowing the original seed value used to start the random number generator. If repeatability of a simulation that uses random methods is desired, then set the Seed property of the Random object at the beginning of the simulation.
Visual Basic has its own random number generator that can be accessed through the rnd() function. Be aware that the Visual Basic and VisualBots random number generators are actually two different random number generators, and if used in the same simulation, would need their own seed values for the simulation to be reproducible.