Deterministic versus Stochastic

Those words are frequently used in Statistics, however most people have some problems with their definitions.

Deterministic processes are those where the results are not going to change, given the same starting condition. Results do not have uncertainty. Optimization is a case of deterministic methods.

Stochastic are clearly Statistics models, where there is some sort of indeterminacy.  There are several directions in which the process may evolve. Simulation is an example of stochastic processes.