  We propose a discretization of classical confocal coordinates. It is based on
a novel characterization thereof as factorizable orthogonal coordinate systems.
Our geometric discretization leads to factorizable discrete nets with a novel
discrete analog of the orthogonality property. A discrete confocal coordinate
system may be constructed geometrically via polarity with respect to a sequence
of classical confocal quadrics. Various sequences correspond to various
discrete parametrizations. The coordinate functions of discrete confocal
quadrics are computed explicitly. The theory is illustrated with a variety of
examples in two and three dimensions. These include confocal coordinate systems
parametrized in terms of Jacobi elliptic functions. Connections with incircular
(IC) nets and a generalized Euler-Poisson-Darboux system are established.
