The Central Processing unit or better known as the CPU is a hardware in a computer that carries out instructions for a computer program.
Ram or Random Accesory memory is computer data storage this device allows things to appear in random order such as cd's dvd's hard disk and memory.
A motherboard is a printed circuit board it holds many circuit like the CPU,memory and Eletric Circuits. And connects to the sound card video cards network cards,hard drives.
The GPU or Graphic Processing Unit for long is an electronic circuit are in embedded systems,mobile phones,personal computers and game consoles. There used in computer graphics (video games).
The Hard Drive is data storage used for retrieving digital information used in rapidly rotating disks