SIM card

A SIM card, or Subscriber Identity Module card, is a small, removable chip used in mobile phones to connect to a cellular network. It stores important information such as the phone number, the user's account details, and security keys that authenticate the device to the network. This allows users to make calls, send texts, and access mobile data services. SIM cards come in different sizes and types, and they can be easily swapped between devices, allowing for flexibility in phone usage and service providers.