What is RSS and how does it work?

I just stumbled upon video called "RSS in Plain English", which explains what RSS feeds are and how they work (and why you might want to use them) in a 3 minute-movie.

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There are two types of Internet users, those that use RSS and those that don't. This video is for the people who could save time using RSS, but don't know where to start.

Source: Commoncraft.com