Learn in the textbookAdvancement of Mobile Communications and Device Technology
DefinitionAn eSIM is a SIM that works by writing contract information to a chip built into the device, so no card has to be inserted or removed.
ExplanationThe contract information is downloaded over the network and written to the chip. There is no waiting for a card, so you can start or switch a line right on the device in your hand.
AnalogyLike replacing the paper membership card in your wallet with one in a smartphone app.
Memory hookThe e stands for embedded.