What is SIM Card or SIM stands for what????

What is "SIM card"?

SIM stands for???

A SIM card is a small card that contains a mobile network subscriber's account information. This allows the phone using the card to attach to a mobile network. About half the size of a typical stamp, the SIM card is most commonly associated with GSM and UMTS handsets. Moving a SIM card from one phone to another allows a subscriber to switch mobile phones without having to contact their mobile network carrier.
SIM cards can also be used by a phone to store limited amounts of data, such as phone numbers and text messages. CDMA based phones typically do not have SIM cards and instead rely on an ESN or MEID.

Also known as: "SIM", "Subscriber Identity Module"

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“SIM” means “subscriber identity module” or “subscriber identification module” and it is an integrated circuit that securely stores the international mobile subscriber identity (IMSI) and the related key used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers).
A SIM circuit is embedded into a removable plastic card. This plastic card is called a "SIM card" and can be transferred between different mobile devices. A SIM card follows certain smart card standards. SIM cards were first made the same size as a credit card (85.60 mm × 53.98 mm × 0.76 mm). The development of physically smaller mobile devices prompted the development of a smaller SIM card, the mini-SIM card. Mini-SIM cards have the same thickness as full-size cards, but their length and width are reduced to 25 mm × 15 mm.
A SIM card contains its unique serial number (ICCID), international mobile subscriber identity (IMSI), security authentication and ciphering information, temporary information related to the local network, a list of the services the user has access to and two passwords: a personal identification number (PIN) for ordinary use and a personal unblocking code (PUK) for PIN unlocking.