A Trekkie born and raised like myself is used to calling each weekly installment of the series an “episode”. Traditionally, these are self-contained narratives, although two-part episodes are familiar to fans of the series, often spanning two separate seasons.
With Dr. Who, however, things get a bit more complicated. An Unearthly Child, for example, aired over four separate dates. Now, following the Trek paradigm, we might call these “episodes”. My colleague adopted this in his first review. The problem then becomes: what do we call the larger stories of which these are components? “Serials”? “Story Arcs”? The BBC DVDs call them “Stories” (urgh). And if we call the larger narrative an “episode,” what of the component segments? Anyway, I thought the best way to answer the question is to take a poll. What should we call the smallest aired segment of each of these stories (e.g. the four parts of An Unearthy Child)?