  This paper surveys Campana's theory of C-pairs (or "geometric orbifolds") in
the complex-analytic setting, to serve as a reference for future work. Written
with a view towards applications in hyperbolicity, rational points, and entire
curves, it introduces the fundamental definitions of C-pair-theory
systematically. In particular, it establishes an appropriate notion of
"morphism", which agrees with notions from the literature in the smooth case,
but is better behaved in the singular setting and has functorial properties
that relate it to minimal model theory.
