What is the difference between the terms "license fee" and "license tax"?

Both parties have favored this court with engaging and scholarly analyses of the distinctions between the various governmental charges that have been exacted under the denominative terms 'license', 'license fee', 'license tax', etc. Thus, as pointed out in Ingels v. Riley, 5 Cal.2d 154, 159, 53 P.2d 939, 103 A.L.R. 1, a charge entitled 'license fee' may be a property tax, an excise or privilege tax, or a regulatory charge imposed under the state's police powers. The inherent distinction between governmental charges designed to produce general revenue and those calculated merely to produce sufficient funds from regulated activities to cover the cost of such regulations was recognized by the framers of the United States Constitution when they provided in Article, I, Section 10, Clause 2 thereof as follows: