INTRODUCTION TO COMPUTERS
Computers have become an integral part of our life and society, their applications ranging from business transactions to personal communications. However, while many people use computers for work and pleasure every day, few have a basic understanding of how computers work.
This unit presents a brief introduction to computers, focusing on what a computer is, how they are organized and what they can do. The knowledge gained from this unit, viz., Introduction to computers, should provide a framework for understanding the basic computer concepts, as well as make you a better consumer of computer technology. We will look at Windows basics(Here I will be talking about Windows XP) and also on how to work with files and folders in Windows Explorer in the coming chapters.
What is a computer?
In simple terms, a computer is an electronic machine capable of performing various arithmetic and logical operations. The computer is also capable of storing information, which can be used later.
A computer can process millions of instructions in a few seconds with high accuracy. Hence a computer can be defined as an automatic electronic machine for performing calculations or controlling operations that are expressible in numerical or logical terms. Computers are very accurate and save time by performing the assigned task very fast. Moreover, unlike human beings,they never get bored.
It is the ability to take instructions in the form of programs and execute them, that distinguishes a computer from a mechanical calculator. While both are able to make computations, a calculator responds simply to immediate input. In fact, most modern calculators are actually computers, with a number of pre-installed programs to help in complex tasks.
Computers accept instructions and data, perform arithmetic and logical operations and produce information. The data fed into the computer is converted into information through processing.
The first electronic computers were developed in the mid-20th century. These were very huge in size., say, the size of a large room, consuming as much power as several hundred modern personal computers (PCs). Modern computers based on integrated circuits are billions of times more capable than the early machines, and occupy a fraction of the space.
The computer has completely changed the way we do our job or organisations operate their businesses. Together with this reason and many more, computers are considered more than just an essential piece of fancy equipment. Whether we know or not, we are forced to use computers in our day to day lives, for doing bank transactions, doing online shopping and many more.
Applications of Computers
Computers are used almost in every sphere of human life including government, industries, medicine, education, law, research, arts and media. Its application is limited only by our imagination.
There are so many applications of computers, that it is impractical to mention all of them. This is the Computer Age and these machines are impacting our lives in many ways. Computers are now becoming faster, more reliable and effective than they had been ever before.
Products from meats to magazines are packed with zebra-striped bar codes that can be read by the computer scanners at supermarket checkout stands to determine prices and help manage inventory. Thus, a detailed receipt of the groceries can be made, which is useful for both the customer and the retail store, especially for the stock control system. This is referred as POS (Point of Sale) transaction where a precise account of all the stocks available is recorded and manipulated.
Health and Medicine
Computers are helping immensely to monitor thee extremely ill in the intensive care unit and provide cross-sectional views of the body. This eliminates the need for hired nurses to watch the patient twenty-four hours a day, which is greatly tiring and error prone. Doctors use computers to assist them in diagnosing certain diseases of the sort. This type of computer is called the Expert System, which is basically a collection of accumulated expertise in a specific area of field. Computers are now able to map, in exquisite detail, the structure of the human cold virus - the first step towards the common cold. Furthermore, computers are used greatly in managing patients, doctors, wards and medicine records, as well as deal with making appointments, scheduling surgeries and other likes.
Farmers use small computers to help with billing, crop information, and cost per acre, and market price checking. Cattle ranchers can also use computers for information about livestock breeding and performance.
It is much more cheaper and effective to teach pilots how to fly in a computerised cockpit or simulators, than in real airplanes. This is because the learning pilots will feel much more relaxed and confident due to the fact that no life is at risk at that moment. Railway engineers can also be given training on how to run a train with the help of a computerised system. Training simulations are relatively cheaper and are always available on one-to-one basis making way for personal training.
Computers are all around us and avoiding them is virtually impossible. We have been exposed in the world of computer advertisements and computer headlines. We interact with computers in our daily lives - whether we are at the cinemas, the school, or the public library.
Hardware and Software
A computer system has two major components, hardware and software.
Hardware refers to all the physical components associated with a computer. The most important is the central processing unit (CPU) or microprocessor. It is the 'brain' of the computer as it does all the calculations and processing. Other hardware devices are monitor, keyboard, mouse, printer, hard disk etc.
Software is a set of instructions/programs, which enables the computer to perform a specific task. An important software called the 'Operating System' is a set of specialized programs which manage the overall operations of the computer. Windows XP is a well-known and widely used operating system. There are other types of software too, known as the application software which are intended to be used for specific tasks such as word processing etc.