  We study in this paper global properties, mainly of topological nature, of
attractors of discrete dynamical systems. We consider the Andronov-Hopf
bifurcation for homeomorphisms of the plane and establish some robustness
properties for attractors of such homeomorphisms. We also give relations
between attractors of flows and quasi-attractors of homeomorphisms in Rn.
Finally, we give a result on the shape (in the sense of Borsuk) of invariant
sets of IFSs on the plane, and make some remarks about the recent theory of
Conley attractors for IFS.
