A computer consists of the major components i.e., Input Unit, Central Processing Unit and Output Unit. Diagrammatically, these components may be presented as follows:
1. Input Unit
Input unit is controlling the various input devices which are used for entering data into the computer. The mostly used input devices are keyboard, mouse, and scanner. Other such devices are magnetic tape, magnetic disk, light pen, bar code reader, smart card reader, etc. Besides, there are other devices which respond to voice and physical touch. Physical touch system is installed at airport for obtaining the online information about departure and arrival of flight. The input unit is responsible for taking input and converting it into binary system.
Central Processing Unit (CPU)
The CPU is the control centre for a computer. It guides, directs and governs its performance. It is the brain of the computer. The main unit inside the computer is the Central Processing Unit. Central Processing Unit is to computer as the brain is to human body. This is used to store program, photos, graphics, and data and obey the instructions in program. It is divided into three subunits:
(a) Control Unit
(b) Memory Unit
(c) Arithmetic Logic Unit (ALU)
Ø Control Unit: Control unit controls and co-ordinates the activities of all the components of the computer. This unit accepts input data and converts it into computer binary system.
Ø Memory Unit: This unit stores data before being actually processed. The data so stored is accessed and processed according to instructions which are also stored in the memory section of computer well before such data is transmitted to the memory from input devices.
Ø Arithmetic and Logic Unit: It is responsible for performing all the arithmetical calculations and computations such as addition, subtraction, division, and multiplication. It also performs logical functions involving comparisons among variable and data items.
v Output unit
After processing the data, it ensures the convertibility of output into human readable form that is understandable by the user. The commonly used output devices include like monitor also called Visual Display Unit, printer etc.
LIMITATIONS OF A COMPUTER
The limitations of computer are depending upon the operating environment they work in. These limitations are given below as :
Ø Cost of Installation: Computer hardware and software needs to be updated from time to time with availability of new versions. As a result heavy cost is incurred to purchase a new hardware and software from time to time.
Ø Cost of Training: To ensure efficient use of computer in accounting, new versions of hardware and software are introduced. This requires training and cost is incurred to train the staff personnel.
Ø Self Decision Making: The computer cannot make a decision like human beings. It is to be guided by the user.
Ø Maintenance: Computer requires to be maintained properly to help maintain its efficiency. It requires a neat, clean and controlled temperature to work efficiently.
Ø Dangers for Health: Extensive use of computer may lead to many health problems such as muscular pain, eyestrain, and backache, etc. This affects adversely the working efficiency and increasing medical expenditure.Follow @Iam_Mtriller