What is a SIM card used for? A SIM card, or a subscriber identity module/subscriber identification module, is a tiny memory card that contains unique information and is linked to a particular network ...

I'm not buying the eSIM hype — physical SIM cards are more reliable and make you less dependent on your cellular carrier.

For many years, mobile phones received cellular service through a physical SIM (subscriber identity module) card that connected your handset to your phone carrier. These physical SIM cards made it ...