The results of experimental investigations of the critical currents and certain nonequilibrium phenomena in thin Sn films of different width w are analyzed. Usually, thin superconducting films are divided into two groups: narrow channels wlambda. A wide transitional region where the condition w>lambda holds with a large margin and at the same time cannot be explained from the standpoint of the theory of the appearance of a vortex state has been found. This shows that the generally accepted

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... rion w \sim lambda for dividing films into wide and narrow does not work. The transition into a wide-film regime, described by the existing theory of the vortex state, is fully completed only for w/lambda(T) > 10-20.