To make sure you never lose your cat, it’s a good idea to have your cat microchipped. Basically this implants a tiny chip under your cat’s skin that contains your contact information. That way if your cat ever gets separated from you, authorities can scan the microchip, get your contact information, and reunite you with your cat.
The cost of microchipping your cat is minimal while the benefits can be enormous. Stories abound of microchipped cats disappearing for months or even years at a time, only to be reunited with their owners when someone scanned their microchip.