Self-similar processes such as fractional Brownian motion are stochastic pr
ocesses that are invariant in distribution under suitable scaling of time a
nd space. These processes can typically be used to model random phenomena w
ith long-range dependence. Naturally, these processes are closely related t
o the notion of renormalization in statistical and high energy physics. The
y are also increasingly important in many other fields of application, as t
here are economics and finance. This paper starts with some basic aspects o
n selfsimilar processes and discusses several topics from the point of view
of probability theory.