The word computer means to compute or to calculate. So a computer is normally considered to be a calculating device.
But, more than 85% of the work done by computer today is of non-mathematical. Hence, a computer may be defined as a device that operates upon data or information. So computer can be defined as a machine in which we can
- Store data or information,
- Process data or information,
- Retrieve data or information
With our requirements
Also, we can say, computer takes facts known as data and, following instructions, it processes these facts to produce information. Computers can process vast amount of data in very short time.
Data and information can be numbers, letters, sounds, pictures and symbols. Pictures and symbols, which a computer produces, are called graphics.
A computer cannot think for itself. It will do exactly as it is told – no more and no less. We often talk about “computer error”, but usually this means human error. If you received a computerised electricity bill for thousand of Rupees when you only use one light bulb, it means that the computer has been given the wrong instructions.
In order to process data computer needs two things hardware and software.
Hardware is the computer machinery – the parts you can see and touch, like the monitor, keyboard and all the electronic devices and circuits inside it.
Software is the instruction or the set of instructions that a computer receives in order to carry out its tasks. All the different sets of instructions are called programs. e.g. songs recorded on the tape. Here songs are software and tape is hardware.
1.3 COMPUTER APPLICATIONS
Computers are now affecting every sphere of human activity and bringing about many changes in industry, government, education, medicine, scientific research, law, social sciences, and even in arts like music and painting. They are presently used, among other application, like
- Design buildings, bridges and machines
- Control space vehicles
- Assist in railway reservation
- Control inventories to minimise material cost
- Grade examinations and process results
- Aid in teaching
- Systematically store and quickly retrieve data on crimes and criminals
- Play games like chess and video games
The areas of applications of computers are confined only by limitations on human creativity and imagination. In fact any task that can be carried out systematically, using a precise step-by-step method, can be performed by a computer.
1.4 CHARACTERISTICS OF COMPUTERS
The interesting characteristics or features of a computer are :
- Easy to operate : Instructions are extremely simple; e.g., add, subtract, read a character, write a character, compare numbers, characters, etc.
- Speed : Most instructions are carried out in less than a millionth of a second.
- Obedient : Instructions are carried out obediently with no questions asked.
- Accuracy : Instructions are carried out without any mistakes.
- Diligence : Unlike human beings, a computer is free from monotony, tiredness, lack of concentration, etc. and hence can work for hours together without creating any error and without complaining.
- Storage Capacity: It can store data as per storage capacity for indefinite time, in permanent storage.
A computer may thus be thought of as a servant who would carry out instructions obediently, uncritically, at a very high speed, and without exhibiting any emotions. As human being, we use judgement based on experience, often on subjective and emotional considerations. Such value judgements often depend on what is called sound “commonsense”.
As opposed to this, a computer to compose music based on rules of composition, but the computer cannot judge the quality of the resultant music. It must be clearly understood that computers are machines, which can be programmed to follow instructions; they don’t have their own priorities and judgements.
Computers are machines, which can help mankind in many ways; but they do not threaten us.
Being obedient without exercising ‘commonsense’ can be very annoying and unproductive.
Take the instance of a Colonel who sent his obedient orderly to post office with the order “Go to the Post Office and buy ten 25 paise stamps”.
The orderly went with the money to the post office and did not return for a long time. the Colonel got worried and went in search of him to the post office and found the orderly standing there with the stamps in his hand.
When the Colonel became angry and asked the orderly why he was standing there, he came the reply that he was ordered to buy ten 25 paise stamps but not ordered to return with them.
A consequence of the uncritical acceptance of orders by a computer is the need to give extensive, detailed, and correct instructions for solving problems. Thus can be quite challenging.
For Video Please visit : https://youtu.be/cx3pQcr9A2Q
For any questions please leave a comment ….