What Does Subscriber Identity Module Card (SIM Card) Mean?
A SIM card (short for subscriber identity module card) is a portable memory chip used in GSM phones. It is a crucial component in mobile telecommunications as it identifies and stores the telephone number and connects the cellphone to the mobile carrier’s network. Since SIM cards also have a (limited) memory element, they can also be used as portable stores for one’s phone contacts.
Techopedia Explains Subscriber Identity Module Card (SIM Card)
There are two competing technologies for mobile phones. The most prevalent one when looking at the worldwide picture is GSM (Global Standard for Mobiles), which is mainly used in Europe, Africa, South America and parts of Asia. Its competitor is CDMA (Code Division Multiple Access), which is more widely used in the USA and parts of China. (Note that most regions do not exclusively use either one or the other, but that the 2 technologies frequently coexist from different mobile providers.)
