A motherboard is the main printed circuit board in a modern computer and has various connectors and sockets for computer components and peripherals. Like a mother it keeps the family of components together and forms the backbone of the personal computer and can be expanded by plugging in additional cards or circuit boards that can perform a range of tasks and functions. Some of these add-on card are things like graphics cards, network interface cards and more. It also holds the RAM modules and CPU which forms the core of the PC. The PC’s hard disk drives also connect to motherboard with special cables and connectors.
Modern motherboards have some of these interfaces built into the board and is referred to as on-board. Some motherboards may come with a basic on-board graphics card for normal use but gamers like to install high performance graphics cards to improve graphics quality and performance.
These add-on cards are plugged into expansion slots on the motherboard which connects to the integrated circuits and CPU via subsystems called buses.