SIM Also known as a SIM card, is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). With the Help Of SIM Card We Can Receive Or Make a phone Call In all over World through Cell Phone . A mobile Phone Connects With Cellular Network (Mobile Tower) through SIM.
SIM Can store contact and Messages. SIM cards are always used on GSM phones; for CDMA phones, they are only needed for newer LTE-capable handsets. SIM cards can also be used in satellite phones, smart watches, computers, or Cameras.