COMPUTER'S_UNIT

Input Unit:-

                       Input unit reads the data and instructions from the user,converts them into computer understandable from and transmit it to the processing unit of computer .It acts as a communication channel between user and the computer .Many input devices such as keyboard,mouse,joystick,light pen etc.froms and input unit.They read different froms of input and converts those input into binary codes which is understood by computer.

Processing Unit:-

                      

                       Processing unit is commonly known as central processing unit(CPU) .It is mounted on the motherboard.It consists of three sub units:Arithmetic and logic unit(ALU).Control unit(CU) and memory unit(CPU)-registers)

                       CPU is the main processing unit which performs all the calculations and directs and controls all the units of the computer system .So,it is also known as brain of computer.

Arithmetic and logic Unit (ALU)

                       This unit performs all the arithmetic operations such as addition,substraction,multiplication and division.It also performs logical operations such as comparision of two or more values or expressions.

Control Unit(CU)

                       This unit management all the computer resource.It executes the computer instructions.It directs the flow of data in the computer i.e. from input device to primary memory and from primary memory to output unit and so on.

Memory Unit

                       This part of CPU consists of the tiny space CPU-registers.These registers are used to put intermediate data during processing.

Output Unit:-

                       The output unit performs work just the reverse of the unit.It intakes the information resulted from the processing unit,and present it to the user in human readable from .Output devices such as monitor,printer,speaker etc froms the output unit.The output produced by the monitor is soft copy output because the output cannot be touched but can be seen.Whereas,the output produced by printer and plotters is hardcopy output because output comes in a paper from which can be touched.

Storage Unit:-

                       The storage unit performs the task of storage the data and instructions .These are basically two classes of storage unit.They are primary storage also called primary memory and the secondary storage also called secondary memory.

Primary Memory

                       This unit is a temporary storage place in the computer.It holds currently running programs,data and instruction .RAM(Random Access Memory)  and ROM(Read Only Memory) are the primary memory of computer .In many cases primary is considered as the part of the processing unit.

Secondary Memory

                      

                       This class of storage unit stores the data and instructions permanently that they are easily accessible in the future .It is also used to record the processed result.Several secondary storage media such as hard disk,floppy disk,zip disk etc from a storage unit.