I walked into a local hardware store, with the following thought in my mind: I need a 5mm metric hex key And I wandered around aimlessly as I do in stores, almost bought some double sided tape for a different project (decided against it), and eventually made it to the place with all the sockets, hex keys, screwdrivers, etc. Words that previously meant nothing to me (Torx, SAE, metric) made sense.
