Micro ATX is a motherboard form factor that measures 244 x 244 mm (9.6 x 9.6 inches). It is designed to provide a balance between size and expandability, making it suitable for compact computer cases while still allowing for multiple expansion slots. Micro ATX motherboards typically feature up to four RAM slots and several PCIe slots for graphics cards and other peripherals. This form factor is popular among gamers and general users who want a smaller system without sacrificing performance or upgrade options.