An eSIM, short for embedded SIM, is a digital SIM (Subscriber Identity Module) card that is embedded directly into a device, such as a smartphone, tablet, or smartwatch. Unlike traditional physical SIM cards that need to be inserted and removed from a device, an eSIM is soldered onto the device's motherboard or integrated into the device's chipset during manufacturing.eSIM technology allows users to activate cellular service on their devices without the need for a physical SIM card. Instead, they can download the necessary network profile and activate their cellular service remotely through a mobile network operator's app or website.