What is wrap aluminum foil around door knob when alone?

Wrapping aluminum foil around a door knob when alone is a safety measure that some people take to protect themselves against intruders. The idea behind this technique is that if someone tries to open the door from the outside, the foil will make a loud noise and alert the person inside. This could potentially scare off the intruder or give the person inside enough time to call for help or escape through a window.

It is important to note that while this method may provide some level of protection, it is not foolproof and should not be relied on as the only means of keeping oneself safe. Investing in a sturdy deadbolt lock or a security system is a more reliable option. It is also recommended to always keep doors and windows locked, especially when alone.