When an Oscar winner starts with their “I’d like to thank the Academy…” speech, one of the things they should thank the academy for is the particular way it counts votes. An Oscar voter votes by ranking their top 5 in each Oscar category (with any remaining candidates ignored). The Academy then has to decide what to do with these lists in order to generate a winner. The Oscar for each category is determined using an ‘instant runoff’ system, which is described in this article by Carl Bialik in the Wall Street Journal. The system is not that familiar, although the article notes it’s used in some municipal and state elections as well. Other vote tabulation systems could quite possibly result in different winners. Those systems are described too, as well as the difficulties that they, in turn, present.
Addendum: The vagaries of the instant runoff, and the related plurality systems in voting, were also discussed on Minnesota Public Radio here.