Tim Hunkin, a marvellous maker, is about to release a series of videos about components. Here’s a microswitch, for example:
But while you’re waiting, you can enjoy his earlier work: Why things go wrong (an hour of early TV - featuring the DC-10 which went very wrong indeed) and both series of Secret Life of Machines. Charming, idiosyncratic, and technically correct. I am of course especially fond of The Word Processor (from the third series, it turns out):
Many more clips here: