What Does 'SIM Card' Actually Mean?

SIM cards have become a universal aspect of modern smartphone usage, but the technology and meaning behind the name dates more than three decades.
Ars Technica

Transfer Samsung Convoy SIM card to iPhone?

I have a base cell phone plan through Verizon, they provided me with a Samsung Convoy 2. Can I install the SIM card from the Convoy 2 in to an unlocked iPhone and continue to use my basic voice / ...