  The management and combination of uncertain, imprecise, fuzzy and even
paradoxical or high conflicting sources of information has always been and
still remains of primal importance for the development of reliable information
fusion systems. In this short survey paper, we present the theory of plausible
and paradoxical reasoning, known as DSmT (Dezert-Smarandache Theory) in
literature, developed for dealing with imprecise, uncertain and potentially
highly conflicting sources of information. DSmT is a new paradigm shift for
information fusion and recent publications have shown the interest and the
potential ability of DSmT to solve fusion problems where Dempster's rule used
in Dempster-Shafer Theory (DST) provides counter-intuitive results or fails to
provide useful result at all. This paper is focused on the foundations of DSmT
and on its main rules of combination (classic, hybrid and Proportional Conflict
Redistribution rules). Shafer's model on which is based DST appears as a
particular and specific case of DSm hybrid model which can be easily handled by
DSmT as well. Several simple but illustrative examples are given throughout
this paper to show the interest and the generality of this new theory.
