eSIM, or embedded SIM (the same as a digital SIM card, electronic SIM card, or virtual SIM card), is a cloud-based mobile number that allows users to activate and manage multiple cellular plans on a single device. It eliminates the need for a physical SIM card and provides the convenience of having multiple cellular providers on a single device. eSIM also offers additional features, such as the ability to add an extra line for traveling abroad and separate data plans for personal and business purposes.