  We use deposition models of kinetic roughening of a growing surface to
introduce the concepts of universality and scaling and to analyze the
qualitative and quantitative role of different parameters. In particular, we
focus on two classes of models where the deposition is accompanied by a local
relaxation process within a distance $\delta$. The models are in the
Edwards-Wilkinson universality class, but the role of $\delta$ is nontrivial.
