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Computer System

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The systematic use of computer hardware, software, firmware and humane ware is known as a computer system. Computer system describes the arrangements of input unit, processing unit, output unit, software system, control panel, users and power supply to the computer system. A computer system may also be defined as the combination of essential components that makes computer to run smoothly.

Basically computer system can be described as the logical structure of computer. It is known as the anatomy of the computer. Like its physical structure anatomical structures of computer also consist of the input unit, processing unit and output devices.

Input Unit

Input unit of a computer are used for receiving data and instructions and communications. An input unit accepts the data and instructions given by the user and it converts the data and instructions from man readable to machine readable code. Some common input devices are mouse, keyboard, scanner, punched cards, disk reader etc.

Central processing Unit

It is the main body of the computer.It consists of three parts:

  1. Memory Unit

    It is a part of Central Processing Unit (CPU) where all the given instruction, data and the results are stored during processing period. By using the unique address we can identify the locations of memory. There are different types of memory among them popular are RAM (Random Access Memory), ROM (Read Only Memory). Memory refers to the electronic holding place for instructions and data where the computers microprocessors can reach quickly. Computer needs memory to store the data and process them.

    We can represent the memory using different units like:
    8 bits= 1 Byte (One Character)
    1024 Byte= 1 Kilo Byte (KB)
    1024 KB= 1 Mega Byte (MB)
    1024 MB= 1GB (Giga Byte)
    1024 GB= 1 TB (Tera Byte)
    1024 TB= 1PB (Peta Byte)
    1024 PB= 1 YB (Yotta yte)
    1024 YB= 1 ZB (Zeta Byte)

    Secondary Memory : It is the supplements of main memory. It is mainly used to transfer data or program from one computer to another computer. It also functions as back up devices which allows backing up the valuable information that you are working on i.e. storing data for future purpose. The most common types of auxiliary storage devices are magnetic tapes, magnetic disks, floppy disks, hard disks etc.

  2. Control Unit

    Control unit is the unit which controls the entire system of computer. That unit directs all operations inside the computer. It will make a proper sequence to direct the data and instructions from the memory to ALU for precise operations performed by ALU. The control unit of the CPU consists of a small, high speed memory used to store temporary results and certain control information. It controls singles to various part of computer.

    The main functions of control unit are given below.

    • It performs the data processing operations with aid of program prepared by the users and send control signals to various parts of the computer system.
    • It gives commands to transfer data from the input device to the memory to arithmetic logic unit.
    • It also transfers the results from ALU to the memory and then to the output devices.
    • It stores program in the memory.
    • It fetches the required instruction from the main storage and analyses each instruction and hence deduces what operation is to be performed.

  3. ALU(Arithmetic and Logical Unit)

    It comprises numbers of accumulators or resisters on its constructions. All the data from the memory directs by control unite gets loaded in ALU. It is one of the very important parts of the CPU. The primary task of the ALU is to perform various arithmetic and logical operations of the program.The arithmetic operations performed are addition, subtraction, multiplication and division. The logical instructions performed are logical AND operation, logical OR operation and logical NOT operation.

Output Unit

It is the unit through which all the results are given out by output devices. There are two types of output soft and hard output. Soft output is the output that displays on the monitor and hard output is the output printed on the paper. The popular output devices are: printers, monitor, plotter, sound etc.

  • The systematic use of computer hardware, software, firmware and humane ware is known as a computer system.
  • Input unit of a computer are used for receiving data and instructions and communications.
  • CPU consists of three parts: Memory Unit, Control Unit, and ALU (Arithmetic- Logic Unit).
  • Output unit is the unit through which all the results are given out by output devices.

Questions and Answers

Click on the questions below to reveal the answers

An expert system is knowledge based system with the capability of reasoning logical approach and come to the conclusion which may be applied in fifth generation computer. E.g. MYCIN is an expert system which is used in the field of medical science.

The system of using more than one processor to solve a particular problem at the same time is called as parallel processing.

The storage unit of computer are:

1 bit 0 or 1
4 bits One nibble
8 bits One byte
1024 bytes One kilobyte (kb)
1024 megabytes One gigabyte (gb)
1024 Gigabyte One terabyte (tb)
1024 Terabyte One petabyte (pb)

The integration of input unit, processing unit, output unit along with necessary software working together to perform the certain task is known as computer system.

The main unit of computer system are:

  • Input unit
  • Output unit 
  • Processing unit

  • Which of the following is not input device?

  • 1024 tera byte equals to:

    1 peta byte
    1 yota byte
    1 mega byte
    1 giga byte
  • What is the fullform of ALU?

    Arithmatical Linear Unit
    Arithmatic Logical Unit
    Arithmatical Logical University
    Arithmatical Local Unit
  • Which unit controls the entire system of computer?

    primary memory
    Arithmatical Logical Unit
    control unit
    memory unit
  • Printers are considered as _________.

    both soft and hard output device
    soft output device
    none of them
    hard output device 
  • What is input?

    Combination of data of differnet parts.
    Collection of data and instructions entered into the computer from Input devices.
    Being aware of its benefits.
    Manipulation of data.
  • What is processing?

    Giving wrong instructions.
    Manipulation of data as per given instructions.
    Result obtain from a computer.
    Being aware of its benefits.
  • What is output?

    One which store large volume of data.
    The result or information obtained from a computer system after data processing.
    Capable of doing different kinds of work.
    Manipulation of data.
  • What is computer system?

    Electronic device.
    Combination of power supply unit , imput device and storage devices.
    Which work at high speed.
    Store very large volume of data.
  • What is GIGO?

  • The data and instruction given to the computer is called __________.

  • The information obtined after the data processing is called __________.

  • __________ is the logical sequence of steps undertaken by a program.

  • What is case?

    outer look of the CPU box.
    transfer data
    transfer the image.
    transfer information.
  • What is CPU?

    input device
    all of above
    device that accepts data and instructions from the input devices.
    output device
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