Apple has gone all in on the eSIM (embedded SIM), a programmable internal version of the SIM (subscriber identity module) card used to ID your phone to cellular networks. With the U.S. models of its iPhone 14 series, Apple has gotten rid of a physical slot for the SIM card. But it also continues to expand eSIM flexibility on other iPhone models and iPads.
For decades, a SIM acted as a secure hardware component that fit into a slot on phones used on most networks worldwide. A SIM provides hard-coded unique ID information for a phone to join a home network or ID itself while roaming. A SIM lets a carrier associate one or more phone numbers and billing information with a given cellular device. (Technically, SIMs were used on one of , the ones that used the GSM.)
