  This paper summarizes the yields and the emission patterns of K+ and of K-
mesons measured in inclusive C+C, Ni+Ni and Au+Au collisions at incident
energies from 0.6 AGeV to 2.0 AGeV using the Kaon Spectrometer KaoS at GSI. For
Ni+Ni collisions at 1.5 and at 1.93 AGeV as well as for Au+Au at 1.5 AGeV
detailed results of the multiplicities, of the inverse slope parameters of the
energy distributions and of the anisotropies in the angular emission patterns
as a function of the collision centrality are presented. When comparing
transport-model calculations to the measured K+ production yields an agreement
is only obtained for a soft nuclear equation of state (compression modulus KN ~
200 MeV). The production of K- mesons at energies around 1 to 2 AGeV is
dominated by the strangeness-exchange reaction K- N <-> pi Y (Y = Lambda,
Sigma) which leads to a coupling between the K- and the K+ yields. However,
both particle species show distinct differences in their emission patterns
suggesting different freeze-out conditions for K+ and for K- mesons.
