SIM card

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"

SMS
SMTP

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