  We study diffraction and interference of indistinguishable particles. We
consider some examples where the wavefunctions and detection probabilities can
be evaluated in an analytical way. The diffraction pattern of a two-particle
system shows notorious differences for the cases of bosons, fermions and
distinguishable particles. In the example of near-field interferometry, the
exchange effects for two-fermion systems lead to the existence of planes at
which the probability of double detection is null. We also discuss the relation
with the approach to systems of identical particles based on correlation
functions. In particular, we shall see that these functions reflect, as in
noise interferometry, the underlying periodic structure of the diffraction
grating.
