  Experimental evidence has been growing for the existence of both molecular
and exotic dibaryons. The former are dominated by hadron and the latter by
quark-gluon degrees of freedom. Exotic dihadrons are of particular interest
because their properties are closely related to the parameters and
non-perturbative properties of QCD models. Molecular structures provide
information about confinement. Purely exotic models, such as bag and valence
quark models, ignore the multi-hadron phase of confinement. Multi-configuration
quark models and R-matrix boundary condition models better represent the medium
range repulsive effects leading to confinement, predicting higher excitation
energies of the exotic resonances. The ^1S_0 exotic predicted at 2.70 GeV mass
has been identified in pp spin observables, implying that there are several
more even and odd parity exotics in the NN system between 2.6 and 3.0 GeV. The
method also predicts exotic strange and doubly strange dibaryons (including a
di-lambda unbound by about 0.13 GeV) and exotics in baryon and meson channels.
The R-matrix formalism also describes the properties of molecular structures
and enables a classification of these into several types. Observed and
predicted examples of each type are discussed, including the recently observed
d'.
