  An introductory survey on the Schroedinger uncertainty relation and its
minimization states is presented with minimal number of formulas and some
historical points. The case of the two canonical observables, position and
momentum, is discussed in greater detail: basic properties of the two subsets
of minimization states (canonical squeezed and coherent states) are reviewed
and compared. The case of two non-canonical observables is breafly outlined.
Stanfard SU(1,1) and SU(2) group-related coherent states can be defined as
states that minimize Schroedinger inequality for the three pairs of generators
simultaneously. The symmetry of the Heisenberg and Schroedinger relations is
also discussed, and two natural generalizations to the cases of several
observables and several states are noted.
