What's the difference between a tv serial and a tv episode?
Reading Wikipedia, it says about one of the Doctor Who companions “Tegan was the longest-serving companion in terms of continuous years on the series (3 years, 1 month), closely followed by Sarah Jane Smith. Jamie McCrimmon was in more episodes and serials than Tegan, while Rose Tyler was in more serials, but not as many episodes.”
How can Rose Tyler be in more serials but not as many episodes? What the hell is a serial? Is it a British telly thing?
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