Introduction – Introduction and Fundamentals of Computer
We are living in an era of Information Technology (IT) where electronic devices like Computers and Mobiles have become an integral part of our lives. The invention of computers has changed the way we work. It has given birth to ‘electronic consciousness‘ amongst the common man, it has changed the working style of business organizations and people drastically. It has been put to use. for all sorts of applications like business, research, medical treatment, education, public crime detection, etc. The invention of computer networks arid Internet has made the ‘global community.
Undoubtedly, it has become necessary for all of us to learn to operate a computer. But, before you learn to operate any machine, you need to have knowledge about it. So, this session aims to give you knowledge about computers and their components.
What is a Computer?
A computer is an electronic data processing device that takes different types of data (text, numbers, graphics, audio, and video) & instructions, stores it, processes it under the directions of the given instructions or software, and gives the required output/information.
Data means facts in the form of numbers, text, images sound, etc. needed to solve or work out a well-defined problem using a computer. Data does not convey any meaning. It is processed or manipulated using the computer to derive information.
Information is processed data or meaningful data.
A computer performs the following operations:
- Input: The data and instructions given to a computer to solve a problem or to perform an operation is called input. For example, to calculate a bill of items using computer, the price of the items purchased and the instruction given to manipulate them are the inputs.
- Storage: Next to input is the storage operation. Computer stores the data and instructions for processing. The processed data or output can also be saved for later use.
- Processing: The process of converting raw data into useful information by working on the data as per given instructions is termed data processing.
- Output: The processed data or the resultant information is the output.
Characteristics of a Computer
All computers, irrespective of their type and size, have common characteristics— speed, reliability, storage capacity, and productivity. The quick-service we expect at the bank, grocery store, stock exchange also depends on the speed of the computer. The computer system possesses the following characteristics:
- Accuracy: All the calculations that are done using the computer are accurate. If errors occur, that are due to mistakes matte by users. The accuracy of the computer is root.
- High speed: The processing speed of a computer is very high. It can perform tasks in few seconds that a normal person would take a few hours to complete. It can carry out thousands of simple mathematical operations in few seconds. Its speed is measured in nanoseconds, i.e., one-billionth (10-9 ) of a second.
- Diligence: Computer is a machine. So, unlike human beings, it does not get tired or bored. It can be operated for hours and is very productive.
- Memory: Computer has the capability to store information— it is called ‘Memory’. Many storage devices such as the floppy disk, CD’s and DVD’s are used to store information for later use.
- Versatility: Computers are versatile. We can perform different tasks using a computer like Internet access, listening to music, education, business and countless other jobs.
- Zero IQ: The computer is not an intelligent machine. It can only do those jobs that it is programmed to do.
Applications of Computer
The application areas of Computer are countless but here are some of the major areas where computers are used:
- Computer Aided Manufacturing (CAM): In modern manufacturing units, most of the machinery is controlled and monitored by computers. They are also used for quality control and testing purposes, e.g., instrument panels are assembled and checked for all functions by computers before they are sent for installation.
- Computer Aided Designing (CAD): Computers are used to design tools, machine parts and even entire machines. Architects use computers to prepare drawings and 3D models of buildings.
- Medicines: Computers are now a days used for diagnosis of various diseases and for maintaining patients database. Medical equipment such as CAT scan, Magnetic Resonance Imaging scan, gamma radiation therapy machines are fully computer controlled. Computers are also used in operation theatres for better analysis during complicated surgery. Using Internet Medical transcription facility we can consult specialized doctors across the world and get benefited from that. Medical research is today totally computer-dependent.
- Weather research and Meteorology: In olden days, man had no ways of knowing how the weather would change from day to day. But today, supercomputers keep analysing data collected by satellites and after performing billions of calculations, these computers give their prediction as to how the weather will change. With the help of computers, Meteorologists can analyse as to how the different parts of the earth are going to be affected in the coming centuries. Geologists are using computers to help them know the probability of finding minerals or oil in an area.
- Education: Use of computer Aided Learning (CAL) or Smart Class System is very useful to understand difficult and abstract topics. Through the use of animation, graphics, sound and text, presentation of lessons is enhanced for the better understanding of the learner. Educational CD-ROMs on various subjects and educational websites are available which provide interactive lessons to the students.
- Business: In business, computers are very useful for Marketing, taking on-line orders, for money transactions, for interacting with customers anywhere in the world. Many business tasks are performed more quickly and efficiently. It helps to reduce the overall cost of their business.
- Banking: In banking computer technology is used for providing Internet banking, ATM facility, credit and debit cards and for maintaining user account data.
- Scientific research: Computers have been the most invaluable tool for research in the field of Physics, Chemistry, Life Sciences and Medicine. Space Research projects at NASA, ARIANE and ISRO are all possible only due to computers.
- Communication: With the continuous advancement in Internet technology and wireless communication, people are able to communicate and Interact with others across the globe through E-mail, chatting, video conferencing and teleconferencing etc.
- Government: Government organisations like Income Tax Department, MTNL, MCD & Development authorities are using computers for providing on-line services to citizens.
- Publishing: Computers are used to design different types of publications like Newspapers, Magazines, Books, Newsletters, Brochures, Pamphlets etc. Soft copy or the digital copy of most of the publications are also available on the Internet in the form of E-books, E-Newspapers etc.
- Entertainment: Computers are widely used in the Entertainment industry for developing computer games, movies, animations, sound recording, music compositions etc.
- Computers in offices : Computers are useful for doing official work like creating different types of documents, preparing Accounts sheets, recording details of employees, sending and receiving E-mail, etc.
- Sports: Sportspersons use simulation software for practising and improving their skills. Computers are also used to aid in umpiring decisions in matches.
- Computers at Home: At home, computers are useful for recreational purposes like watching movies, listening to music, for interacting with friends through facebook, twitter etc. and for playing computer games.
- Mobile computing: Through the mobile computing technology, it is possible to transmit data, voice and video via a computer or any other wireless enabled device without physical link. It involves Mobile communication, Mobile hardware and Mobile software. More and more users and businesses now a days use smartphones, laptops and PDA as communication tools.
- Social Media: Using social media like Facebook, Twitter, Whats app etc. people are able to create, share or exchange information, career interests, ideas, and pictures/videos in a highly interactive manner using the virtual communities and networks
Components of a Computer System
Computer system consists of four main components:
|The physical components of a computer system are termed hardware. An input device, output device, C.P.U. are examples of computer hardware.||Software is a set of programs that govern the operations of a computer system and makes the hardware run. Windows 98, MS-DOC, MS-Word, AutoCAD, etc. are examples of software.||The microprograms or system programs that are permanently stored on chips during the manufacturing of computers for controlling internal system operations are termed firmware.||A computer cannot operate on its own. If requires human Intervention to function. It performs any task as per the data and instructions are given by the user.|
Each of these components plays a significant role in the functioning of the computer system. It cannot function in the absence of any of them.
A Computer network is composed of multiple connected computers that communicate over a wired or wireless medium to share data and other resources.
When multiple computers are interconnected through wired or wireless medium to share data and other resources, it is termed a Computer Network.
There are different kinds of computer networks. They may be very small and simple as in a room or maybe as complex as a global network or Internet. Also, there may be wired, wireless or satellite connections between computers. We need to determine, which network will suit our or organization’s needs best.
Basic Components of a Computer Network
A network is formed using many hardware devices and specialized software to control the working of a network and to take care of the data being transmitted. Complex networks have some more specialized devices. A Local Area Network comprises the following basic components:
- Server – A server is a computer to which all other computers of a network are connected. It provides hardware and software services to other computers in the network.
- Hub or ‘Switch’ – Switches and hubs are devices to which computers, printers, and other networking devices are connected.
- Workstation – A computer connected to server is called as a workstation.
- Network Operating System – A Network Operating System is a set of programs that allow a computer to serve requests from other computers for data and other resources such as printer and file systems. Examples of Network Operating Systems are Windows 2000, Windows NT, Linux, Macintosh, Netware, OS/2 etc.
Types of Computer Networks
Networks are classified into the following types on the basis of the geographical area covered by them:
Local Area Network (LAN)
A network that spreads over a small area or a group of nearby buildings is called a Local Area Network. It is owned, controlled, and managed by a single person or organization. The computers in a LAN are mostly connected through Ethernet cables.
Metropolitan Area Network (MAN)
It is a network that connects two or more local area networks or campus area networks together but does not extend beyond the boundaries of the immediate town/city. Its physical area is larger than a LAN but smaller than a WAN. It is owned and operated by a single entity such as a government body or large corporation.
Wide Area Network (WAN)
This type of network spans in a relatively large geographical area (diameter of about 200 km ). It geographically-dispersed collection of smaller networks like LANs, MANS, and CANS. A network device called LANs to a WAN.
Unlike LANs, most WANs (like the Internet) are not owned by any one organization but rather exist under collective or distributed ownership and management. WANs use satellite communication.
An intranet is a private network, accessible only to an organization’s staff. It provides a wide range of information and services from the organization’s internal IT systems that would not be available from the Internet.
The Internet is a system of linked networks that are worldwide in scope and facilitate data communication services such as remote login, file transfer, electronic mail, the World Wide Web, and newsgroups. With the rise in demand for connectivity, the Internet has become a communications highway for millions of users. The Internet was initially restricted to military and academic institutions, but now it is a full-fledged conduit for any and all forms of information and commerce. Internet websites now provide personal, educational, political, and economic resources to every corner of the planet.
Advantages of the Internet
The Internet or the World Wide Web is indeed a wonderful and amazing addition to our lives. The Internet can be known as a kind of global meeting place where people from all parts of the world can come together. The major advantages of the internet are:
- E-mail: E-mail is an online correspondence system. With e-mail you can send and receive instant electronic messages, which works like writing letters.
- Access Information: The Internet is a virtual treasure trove of information. The ‘search engines’ on the Internet can help you to find data on any subject that you need.
- Shopping: Along with getting information on the Internet, you can also shop online. There are many online stores and sites that can be used to look for products as well as buy them using your debit or credit card.
- Online Chat: There are many ‘chat rooms’ on the web that can be accessed to meet new people, make new friends, as well as to stay in touch with old friends.
- Downloading Software: You can download innumerable, game, music, videos, movies, host of other entertainment software from the Internet, most of which are free.
Computer programs are sets of logical instructions written in a computer language like C, Java Python, etc., to make a computer perform certain tasks.
Programs and Data
Programs process data that you provide as an input to your computer. This data can be in the form of text, graphics, audio, or video depending on the type of program. For example, a calculator is a program that requires input in the form of numbers. Similarly, Sound Recorder is a program that requires input in the form of audio. When the program receives the data, it processes the data and displays the output on the screen. You can save this output in a file. Depending on the type of data that a file contains, the file is classified as an audio file, a text file, a graphics file, or a video file.
An operating system (abbreviated as “OS”) is the system software that, after being initially loaded into the computer by a boot program, manages all the other programs in a computer. The application programs make use of the Operating System by making requests for services through a defined Application Program Interface (API). In addition, users can interact directly with the operating system through a user interface such as a command language or a Graphical User Interface (GUI).