Smartcards and SIM cards

[countrygirl]

What is the difference between a smartcard and a SIM card in cell phone because i have 3 phones right now. One takes a smartcard one takes a SIM card and the third one does not take either one. Can someone please tell me the difference?

 

[Harald Kapp]

Welcome to our forum.

A smart card is any chipcard that has a built-in chip. This can range from some simple memory to sophisticated crypto-processors.
A SIM card (SIM=Subscriber Identity Module) is a special type of smart card with a defined form factor (the typical oblong shape with one beveled corner) which is specifically used to identify a mobile communication participant.

Cell phones (almost?) always use SIM cards. If you cell phone doesn't accept your SIM card, check the size (there are SIMs, MiniSIMs, MicroSIMs, NanoSims). If the size fits, check your SIM card in another phone. If that works, check another SIM card in your phone. SIM cards as well as phones can be defect.

 

[Gryd3]

Welcome to our forum.
Cell phones (almost?) always use SIM cards. If you cell phone doesn't accept your SIM card, check the size (there are SIMs, MiniSIMs, MicroSIMs, NanoSims). If the size fits, check your SIM card in another phone. If that works, check another SIM card in your phone. SIM cards as well as phones can be defect.

SIM cards are also tied to specific carriers. I don't believe you can use an AT&T SIM card with any other carrier than AT&T.
Phones can also be locked multiple ways to a specific Carriers SIM card, or a specific SIM card as a security measure... ie, you lock your phone to your SIM card, so if stolen no other SIM card will work. Or companies like Rogers, AT&T, Telus will lock the phones they sell to their own network so you cannot put in a SIM card from a competing carrier to use your phone.