That’s Shocking
Amazingly enough, as we walk around we are constantly gaining or shedding extra electrons. Most people know this process as a static shock. If you are the type of person who does not like shocks, here is a tip: drag your fingers along a different surface before you touch the doorknob
In this instance, someone seems to have electrified their doorknob. Possibly, this was a Home Alone type of prank gone wrong or a seriously bad installation job. New homeowners are tempted to do lots of things themselves to save a buck or two. Maybe this person didn’t know to check for electrical wires when they were drilling in the wall.