  Confocal conics form an orthogonal net. Supplementing this net with one of
the following: 1) the net of Cartesian coordinate lines aligned along the
principal axes of conics, 2) the net of Apollonian pencils of circles whose
foci coincide with the foci of conics, 3) the net of tangents to a conic of the
confocal family, we get a planar 4-web. We show that each of these 4-webs is of
maximal rank and characterize confocal conics from the web theory viewpoint.
