INTRODUCTION TO COMPUTER

DEFINITION OF COMPUTER

  • It is an electronic device that computes and process the data
  • It accepts input data manipulates and transforms all kinds of data to produce output at a fast speed without any mistake.
  • It computes itself cannot do any activity because it doesn’t have the thinking power.
  • Therefore, to perform a task the computer requires necessary instruction in the most detailed form. This set of instructions is called program in a language to perform a task by the computer.

ADVANTAGES OF COMPUTER

  • A computer has a high rate of processing speed, so that it can produce results so quickly even for any complicated problem.
  • A large volume of data and their information can be stored in its memory and also any data can be retrieved immediately for processing.
  • Solution of a complicated problem is obtained in a fraction of second

LIMITATIONS OF A COMPUTER

  • It does not have any thinking power.
  • Trained personnel are necessary to operate the computer.
  • A computer will not rectify any errors committed in the program and data.
  • High initial cost.

APPLICATIONS OF COMPUTER

  • Communication networks such as train tickets, flight tickets booking, email, fax, Internet, cellular, phone etc., usage is fast.
  • Bank accounting, pay bill preparations.
  • In research institutes to solve any complicated problems with high accuracy.
  • Control of rocket launching, spacecraft.
  • Weather forecasting

A computer consists of five basic functional units.

  1. Input unit
  2. Output unit
  3. Control unit
  4. Memory unit
  5. Arithmetic and logical unit
CPU

It is the heart of the computer system. It consists of memory units, control unit, and arithmetic and logical unit. Actual computation is carried out there.

INPUT UNIT
  • It is a part of the computer to which the information is fed.
  • The function of the input unit is to read the information contained in the program and transmit to the CPU                                                         Eg:  Keyboard, Mouse.
OUTPUT UNIT
  • Output unit which is used to produce the results in a human readable form.                                                                                                                    Eg: Monitor, Printers.
CONTROL UNIT
  • It plays an overall coordinating role in the entire system. It controls the input and output units directly.
MEMORY UNIT
  • The memory of the CPU is the section where the Programs and data are stored after they are fed in through the input unit.
ARITHMETIC AND LOGICAL UNIT
  • In arithmetic and logical unit the computer process both arithmetic and logical operation and calculate in numerical.
 COMPUTER HARDWARE
  •  All physical components used for input, processing, output and storage device are known as Hardware.                                                        Eg:  Keyboard, Monitor and CPU
COMPUTER SOFTWARE
  • A set of programs used to perform a specific task.
  • It is a collection of instructions used to perform a specific task
TYPES OF SOFTWARE
  • Application software
  • System software
APPLICATION SOFTWARE
  • It is actually a set of programs that are written using a specific Programming language to fulfill the needs of the user.
SYSTEM  SOFTWARE
  • Set of programs to perform a variety of system functions such as file editing, memory management and input management.                        Eg:  Operating system
MEMORY
  • It is a section where all the data and other information of stored for later use
  • Any information or data is stored in the memory only in the form of binary digits, which consists of zeros and ones.                                  There are two types of memories
  1. Main memory
  2. Secondary memory or Auxiliary memory
MAIN MEMORY
  • This memory which is directly connected to the CPU circuitry and holds it’s storage in a temporary nature is known as main memory
  • Storage capacity limited.
  • It consists of core or semiconductor cells.
SECONDARY MEMORY
  • The storage device which is permanent in nature
  • The program and data which have any future use are stored in secondary memory, so that any of them can be transferred into main memory, when necessary.
  • Writing, erasing and rewriting for any number of times is possible in an auxiliary storage unit.
HARD DISK
  • The hard disk is a PC is permanently fixed in it and has a storage capacity of 10 GB and or higher. Hard disk is divided into number of sections or segments. The segments are known as directories.
OPERATING SYSTEM
  • Operating system that controls the hardware is a system software
  •  Interface between the user and the system.
  • It is also defined to be the program that instructs the PC how to work with its various components.
  • Operating system manages the activities of the computer system.
  • As soon as you switch on the computer a part of the operating system is called supervisor get loaded into the main memory.
  • The operating system can be stored in the hard disk
  • Supervisor load the other product of the operating system as and when needed.
FUNCTION OF OPERATING SYSTEM
  • It loads itself into the computer memory
  • It controls and coordinate the entire computer system.
  • It loads user programs and data into Computer memory

    Eg:  MS DOS, WINDOWS, UNIX, LINUX

 

  

Leave a Reply

Your email address will not be published. Required fields are marked *