computer
- 1. Computers are machines that perform tasks or calculations according to a set of instructions, or programs. The first fully electronic computers, introduced in the 1940s, were huge machines that required teams of people to operate. Compared to those early machines, today's computers are amazing. Not only are they thousands of times faster, they can fit on your desk, on your lap, or even in your pocket.
- 3. The system unit is the core of a computer system. Usually it's a rectangular box placed on or underneath your desk. Inside this box are many electronic components that process information. The most important of these components is the central processing unit (CPU), or microprocessor, which acts as the "brain" of your computer.
- 4. A mouse is a small device used to point to and select items on your computer screen. Although mice come in many shapes, the typical mouse does look a bit like an actual mouse. It's small, oblong, and connected to the system unit by a long wire that resembles a tail. Some newer mice are wireless. Mouse pointers
- 5. A keyboard is used mainly for typing text into your computer. Like the keyboard on a typewriter, it has keys for letters and numbers, but it also has special keys: The function keys, found on the top row, perform different functions depending on where they are used. The numeric keypad, located on the right side of most keyboards, allows you to enter numbers quickly. The navigation keys, such as the arrow keys, allow you to move your position within a document or webpage. Keyboard
- 6. A monitordisplays information in visual form, using text and graphics. The portion of the monitor that displays the information is called the screen. Like a television screen, a computer screen can show still or moving pictures. There are two basic types of monitors: CRT (cathode ray tube) monitors and the newer LCD (liquid crystal display) monitors. Both types produce sharp images, but LCD monitors have the advantage of being much thinner and lighter. LCD monitor (left); CRT monitor (right)
- 7. A printer transfers data from a computer onto paper. You don't need a printer to use your computer, but having one allows you to print e-mail, cards, invitations, announcements, and other material. Many people also like being able to print their own photos at home. The two main types of printers are inkjet printers and laser printers. Inkjet printers are the most popular printers for the home. They can print in black and white or in full color and can produce high-quality photographs when used with special paper. Laser printers are faster and generally better able to handle heavy use. Inkjet printer (left); laser printer (right)
- 8. Speakers are used to play sound. They can be built into the system unit or connected with cables. Speakers allow you to listen to music and hear sound effects from your computer.
- 9. To connect our computer to the Internet, you need a modem. A modem is a device that sends and receives computer information over a telephone line or high- speed cable. Modems are sometimes built into the system unit, but higher-speed modems are usually separate components. Cable modem
- 10. INTRODUCTION TO INTERNET The Internet has actually been in existence for quite a long time. Originally used as a means of keeping communication channels open between military bases in various parts of the United States of America, it was at that stage a small network of slow modems connected to mainframe computers. The network was extended by connecting computers from universities around America and it was not long before university staff were using the system to send messages to each other. The idea was used in other countries and it was not long before countries started connecting their networks to one another and. From these beginnings in the mid-1960s the Internet has grown to include a number of methods, or protocols, for communicating via computer.
- 11. Before the wide spread of internetworking that led to the Internet, most communication networks were limited by their nature to only allow communications between the stations on the local network and the prevalent computer networking method was based on the central mainframe computer model. Several research programs began to explore and articulate principles of networking between physically separate networks, leading to the development of the packet switching model of digital networking. These research efforts included those of the laboratories of Donald Davies (NPL), Paul Baran (RAND Corporation), and Leonard Klein rock at MIT and at UCLA. The research led to the development of several packet- switched networking solutions in the late 1960s and 1970s, including ARPANET and the X.25 protocols. Additionally, public access and hobbyist networking systems grew in popularity, including unix-to-unix copy (UUCP) and FidoNet. They were however still disjointed separate networks, served only by limited gateways between networks. This led to the application of packet switching to develop a protocol for internetworking, where multiple different networks could be joined together into a super- framework of networks. By defining a simple common network system, the Internet Protocol Suite, the concept of the network could be separated from its physical implementation.
- 12. Advantages Communication: With Internet we can communicate in a fraction of second with a person who is sitting in the other part of the world. Today for better communication, we can avail the facilities of e-mail; we can chat for hours with our loved ones. Information Information is probably the biggest advantage internet is offering. The Internet is a virtual treasure trove of information. Any kind of information on any topic under the sun is available on the Internet. Entertainment Entertainment is another popular raison d'être why many people prefer to surf the Internet Downloading games, visiting chat rooms or just surfing the Web are some of the uses people have discovered. Services Many services are now provided on the internet such as online banking, job seeking, purchasing tickets for your favorite movies, guidance services on array of topics engulfing the every aspect of life, and hotel reservations. Often these services are not available off-line and can cost you more. E-Commerce Ecommerce is the concept used for any type of commercial maneuvering, or business deals that involves the transfer of information across the globe via Internet.
- 13. Theft of Personal information If you use the Internet, you may be facing grave danger as your personal information such as name, address, credit card number etc. can be accessed by other culprits to make your problems worse. Spamming: Spamming refers to sending unwanted e-mails in bulk, which provide no purpose and needlessly obstruct the entire system. Such illegal activities can be very frustrating for you, and so instead of just ignoring it, you should make an effort to try and stop these activities so that using the Internet can become that much safer. Virus threat Virus is nothing but a program which disrupts the normal functioning of your computer systems. Computers attached to internet are more prone to virus attacks and they can end up into crashing your whole hard disk, causing you considerable headache. Pornography: This is perhaps the biggest threat related to your children’s healthy mental life. A very serious issue concerning the Internet. There are thousands of pornographic sites on the Internet that can be easily found and can be a detrimental factor to letting children use the Internet.
- 14. Network that led to Internet Promoted to the head of the information processing office at DARPA, Robert Taylor intended to realize Licklider's ideas of an interconnected networking system. Bringing in Larry Roberts from MIT, he initiated a project to build such a network. The first ARPANET link was established between the University of California, Los Angeles and the Stanford Research Institute on 22:30 hours on October 29, 1969. By December 5, 1969, a 4-node network was connected by adding the University of Utah
- 15. The World Wide Web (usually called the web, or web) is a gigantic storehouse of information. The web is the most popular part of the Internet, partly because it displays most information in a visually appealing format. Headlines, text, and pictures can be combined on a single webpage—much like a page in a magazine—along with sounds and animation. A website is a collection of interconnected WebPages. The web contains millions of websites and billions of WebPages.
- 16. E-MAIL E-mail (short for electronic mail) is a convenient way to communicate with others. When you send an e-mail message, it arrives almost instantly in the recipient's e-mail inbox. You can send e-mail to many people simultaneously, and you can save, print, and forward e-mail to others. You can send almost any type of file in an e-mail message, including documents, pictures, and music files. And with e-mail, you don't need a postage stamp!
- 17. Instant messaging Instant messaging is like having a real-time conversation with another person or a group of people. When you type and send an instant message, the message is immediately visible to all participants. Unlike e-mail, all participants have to be online (connected to the Internet) and in front of their computers at the same time. Communicating by means of instant messaging is called chatting.
- 18. If you have a digital camera, you can move your pictures from the camera to your computer. Then you can print them, create slide shows, or share them with others by e-mail or by posting them on a website. You can also listen to music on your computer, either by importing music from audio CDs or by purchasing songs from a music website. Or, you can tune in to one of the thousands of radio stations that broadcast over the Internet. If your computer comes with a DVD player, you can watch movies too
- 19. GAMING Thousands of computer games in every conceivable category are available to entertain you. Get behind the wheel of a car, battle frightening creatures in a dungeon, or control civilizations and empires! Many games allow you to compete with other players around the world through the Internet. Windows includes a variety of card games, puzzle games, and strategy games.
- 20. BY: RAJA MEHTA