SIM card

Integrated circuit card for mobile devices

A SIM card or SIM (subscriber identity module) is a type of integrated circuit, often in the form of a smart card. They are intended to securely store an international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephone devices (such as mobile phones, tablets, and laptops). SIMs are also able to run apps and to store arbitrary information like address book contact information, and may be protected using a PIN code to prevent unauthorized use.

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