Explania that clearly explains a part of our daily computer uses that we often don't think about at all. In How Can Cookies Make Your Surfing Experience Convenient? we learn what browser cookies do for us. It's not the most comprehensive explanation you'll find, but it is a good primer on the topic.
How can cookies make your surfing experience convenient? - Explania
Applications for Education
One of the adult ed courses that I commonly see advertised in local newsletters is "introduction to computers" and or "introduction to the web." Videos like this one from Explania could be nice little primers on for topics in those introductory courses.