An eSIM (embedded SIM) is a small chip inside a device that can be programmed with a cellular network's information. Instead of using a physical SIM card, eSIMs are built into the device and can be activated remotely.

eSIM plans are mobile plans that support eSIM technology. To use an eSIM plan, your device must be compatible with eSIMs, and you will need to have an eSIM profile installed on your device. This profile contains the information needed to connect to the cellular network and activate the eSIM.

To activate an eSIM plan, you typically need to scan a QR code provided by your carrier or enter an activation code. Once activated, your device will connect to the cellular network and be ready to use.

eSIM plans offer several benefits, including the ability to activate a mobile plan remotely, switch between carriers easily, and use multiple numbers on one device. However, not all carriers support eSIM technology, and not all devices are compatible with eSIMs. It's important to check with your carrier and device manufacturer to see if eSIMs are supported before trying to activate an eSIM plan.