SIM card
Sign in to savesmartcard for cellular devices containing authentication information necessary for connecting to the cell network
AI overview
A SIM card is a small smart card that goes inside your phone and contains the information needed to connect to your cellular network and identify your account. It matters because without it, your phone can't authenticate with your carrier to make calls, send texts, or use mobile data.
AI-generated from the Wikipedia summary — may contain errors.
Article
A typical SIM card (mini-SIM with micro-SIM cutout)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.
These SIM cards are always used on GSM phones; for CDMA phones, they are needed only for LTE-capable handsets. SIM cards are also used in various satellite phones, smart watches, computers, or cameras. The first SIM cards were the size of credit and bank cards; sizes were reduced several times over the years, usually keeping electrical contacts the same, to fit smaller-sized devices. SIMs are transferable between different mobile devices by removing the card itself.