A Micro SIM is a type of SIM card that is smaller than a standard SIM card but larger than a Nano SIM. It measures 15mm x 12mm and is used in various mobile devices, including smartphones and tablets. The Micro SIM was introduced to save space in devices while still providing the necessary connectivity for cellular networks. Micro SIM cards contain the same essential components as standard SIM cards, such as the Integrated Circuit (IC) that stores user data and network information. They are often used in devices that require a compact design, allowing manufacturers to create thinner and lighter gadgets without sacrificing functionality.