Different units or module in computer system communicate with each other with the help of bus.The central processing unit is also connected to the rest of the system through system bus. Through system bus, data or information gets transferred between the CPU and the other components of the system. Here in this gate study material for computer science exam I am telling about three main types of buses that a system contains. These buses are

Data Bus: Data bus is generally used to transfer the data between main memory and central processing unit.
Address Bus: When the processor wants to fetch the data from memory then it puts the address on address bus.

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