A motherboard is the main circuit board in a computer, connecting all components and allowing them to communicate. Key features include the CPU socket, which holds the processor, and RAM slots for memory modules. It also has expansion slots for additional cards, such as graphics cards and sound cards, enhancing the system's capabilities. Other important features are the chipset, which manages data flow between the processor and other components, and various ports for connectivity, including USB and HDMI. Additionally, motherboards come with built-in storage connectors like SATA and M.2 for hard drives and solid-state drives, ensuring efficient data access.