The theory of stochastic processes that were dealt in this work can be utilised not only in pure nature sciences, like physics, biology, theory of reliability, but also in many technical and operational branches, like telecommunication network management, computer network control, and last but not least, in many branches of real life, like economy, business, commerce, logistic, etc. Some utilisation examples and practical applications and consequences were mentioned, too. May a reader of this work will find further application.