Gauge theories are of the most interest for physicists in the recent decades. A system is said to possess gauge symmetry if the action, as well as the equations of motion, do not change under transformations which include arbitrary functions of time. From the canonical viewpoint one needs to find the generators of the symmetry and their algebra in order to study the effect of that symmetry on the physical variables. For gauge theories, we know from the Dirac conjecture that all of the first 14pt; TEXT-ALIGN: justify" Key words: Gauge theories, Generating function of Gauge transformations, Polyakov string, Reparameterization