MOTHERBOARD
motherboard is a main board in system unit. it contains chips, integerated circuits,  and transistors. also its called as System board.
                                 
                                   PRCESSOR
The processor is the most impotant part of the computer. it process the data and controls the computer.
powerful computers used as servers often have more than one processor.
                                
                                  CENTRAL PROCESSING UNIT
CPU is the brain of the computer system. it contols the computer operations. such as   make decisons, makes all sorts of  calculations etc.
it function

• converts data into information
• contol center

• set of eloctranic circuitry that executes stored program instructions.