21 Everyday Things You Never Knew Even Had A Purpose

What about this thick bit found on many cables?

Those little cylinder-shaped lumps are ferrite cores or chokes, and they're essentially just chunks of magnetic iron oxide that are there to suppress high-frequency electromagnetic interference.Have you ever heard weird interference when your cell phone goes off too close to a speaker? Well, ferrite cores are there to keep that from happening to your monitors, power supplies, and everything else.