No matter what sort of work you do, at some point you end up needing a sharp edge. I usually have a small folding knife with me for just such occasions. Sometimes, other people need the sharp edge so I lend them my knife. Now, they can open it fore sure, but almost everyone is confused on how to close the knife.

I even had one co-worker who ended up disassembling my knife trying to figure out how to close the darn thing!

It's just a skill people seem to not have and they should as it's a very popular design.

I have included a link to a video which illustrates how to close a knife. The video is not mine.