A CPU socket is a physical interface on a computer's motherboard that allows a central processing unit (CPU) to be installed and connected. It provides the necessary electrical connections and mechanical support for the CPU, enabling it to communicate with other components of the computer. Different types of CPU sockets are designed for specific CPU models, ensuring compatibility. Each CPU socket has a unique layout and pin configuration, which means that a CPU can only fit into its designated socket type. Common socket types include LGA, PGA, and BGA, each serving different families of processors from manufacturers like Intel and AMD.