  In this article old and new relations between gauge fields and strings are
discussed. We add new arguments that the Yang Mills theories must be described
by the non-critical strings in the five dimensional curved space. The physical
meaning of the fifth dimension is that of the renormalization scale represented
by the Liouville field. We analyze the meaning of the zigzag symmetry and show
that it is likely to be present if there is a minimal supersymmetry on the
world sheet. We also present the new string backgrounds which may be relevant
for the description of the ordinary bosonic Yang-Mills theories. The article is
written on the occasion of the 40-th anniversary of the IHES.
