  Magnetic strings are defined as infinitely thin surfaces which are closed in
the vacuum and can be open on an external monopole trajectory (that is, defined
by 't Hooft loop). We review briefly lattice data on the magnetic strings which
refer mostly to SU(2) and SU(3) pure Yang-Mills theories and concentrate on
implications of the strings for the Yang-Mills plasma. We argue that magnetic
strings might be a liquid component of the Yang-Mills plasma and suggest tests
of this hypothesis.
