Internet, Wi-Fi and phone
eSIM
Abbreviation for embedded Subscriber Identity Module
In short and in plain language
An eSIM is a card for the mobile network that is built into the device.
So you do not put a card in.
Instead, you load data from your provider onto the device. Often you do this by scanning a code.
Definition
An eSIM is a SIM that is built into the device. Instead of inserting a card, you load a profile from the mobile provider onto the device. This often works via a QR code.