A computer is also called as a data processor, because it can receive, store, process and retrieve any kind of data. For instance, we can use computers to store the details of employees in an organization, which include personal details, pay details, and leave details. The stored information can be retrieved and used later to analyze the performance of employees and to print pay slips for them.
Computers are everywhere. Every day we come in contact with and use dozens of computers, sometimes without even knowing it. When we stop by the ATM to withdraw cash, a computer performs the calculations, updates our account and dispense cash with the help of mechanical parts controlled by it. At a supermarket, computers are used to bill the groceries we purchase. They can also be used to provide us real-time weather reports; driving directions, etc. In modern vehicles, computers can be used to notify emergency response teams if the passengers get caught in an accident.
Two important characteristics of a computer are: speed and accuracy. Computers operate at very high speed and execute several million instructions in one second. They also perform their operations with a very high degree of consistent accuracy. Because of these features, computers are used in various fields, where there is a need for doing calculations or data processing speedily, accurately and diligently. Some of the tasks that can be automated using computers are listed below:
- Preparing documents and performing data processing jobs in offices and homes
- Maintaining accounts and transfer funds in banks
- Preparing salary slips for employees in an office
- Booking tickets in the transportation sector, e.g., Railways, Airlines etc.
- Regulating traffic lights on roads
- Control machines in factories, robotics and modern automobiles
- Design buildings, roads etc.
- Regulating electronic appliances such as Air Conditioners, TVs, VCRs, etc.
- Forecasting weather
- Guiding and operating defense equipment
- Performing scientific and industrial research
Now-a-days computer is playing a main role in everyday life of human being. It has become the need of people just like television, telephone or other electronic devices at home. It is used to solve the problems faced by human problems quickly and accurately. Some of the important characteristics of a computer are described below:
Speed:
A computer is a very high speed electronic device. The operations on data stored in a computer are performed using electronic circuits available in a computer. The data and instructions flow along these circuits with high speed as fast as the speed of light.
Moreover, computers can perform millions of operations on data in one second. The speed of a computer is usually measured in terms of Mega Hertz (MHz) or Giga hertz (GHz). Hertz is the standard unit of measuring frequency. One Hertz is equal to one cycle per second. Radio frequencies are usually measured in Kilo Hertz, Mega Hertz, or Giga Hertz.
Solves Arithmetical and Logical Operations
A computer can perform arithmetical and logical operations for solving any problem. Arithmetic operations include performing addition, subtraction, multiplication and division on numerical data. Logical operation include inclusion, exclusion or negation of values resulted from an arithmetic operation. It also includes performing comparison on numerical as well as alphabetical data.
Accuracy:
In addition to being very fast, computers operate with high accuracy. They produce accurate output provided that the correct input and required set of instructions are given to them. It means that the output is totally dependant on the given instructions and input data. If input data is incorrect then the resultant output will also be incorrect. In computer terminology it is known as garbage-in garbage-out.
Reliability:
The electronic components used in modern computers have very low failure rate. A modern computer can perform more complicated calculations without any difficulty and produces consistent (reliable) results.
Storage:
A computer has internal storage (primary) as well as external (secondary) storage. In secondary storage, a large amount of data and programs (set of instructions) can be stored for future use. The stored data and programs are available any time for processing.
Retrieves Data and Programs Instantly:
The data and program stored on the storage media can be retrieved quickly in a fraction of a second for further processing.
Automates the Manual Process:
A computer can automatically perform operations without the interference of the user during its execution. It controls automatically different devices attached to it. It executes the program instructions one by one sequentially.
Versatility:
Versatile means flexible. Modern computers can perform different kind of tasks one at a time or simultaneously. This is the most important feature of a computer. A computer can be used for playing game, and at the same time it can be used for composing and sending emails. In colleges and universities, computers are use to deliver lectures to the students.
Channel of Communication:
Today computers are mostly used to exchange messages or data through computer networks all over the world. For example, the information can be shared among users of the Internet with the help of a computer.
Diligence:
A computer can continually work for hours together without making any mistake. It does not get tired even after working for long hours. It performs various operations with accuracy and speed.
Has No Feelings:
Computer is an electronic machine. It has no feelings. It gets connected to the external world on the basis of instructions given to it. As a human being, we make decisions based on our feelings, acquired knowledge and prior experience in our daily life. But computers cannot make such decision on their own. They decide their path of execution totally based on instructions given to them.
Consistency:
People often gets tired or bored in doing the same task again and agin. For instance, a teacher may get bored while delivering the same lecture to various groups of students in a class room environment again and again. On the contrary, computers can perform doing certain operations consistently (again and again) without loosing its accuracy.
Precision:
Computers are not only fast and consistent but they also perform operations accurately and precisely. For example, in manual calculations and rounding fractional values, human beings tend to make mistakes. But, using computer, we can maintain the accuracy and precision to a great extent.
