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What is Internet |
What is the Internet?A large number of computers inter-linked by various means from the Internet. A large web is created, which is independent of any agency or computer server. The sun never sets on the internet global community. The Internet runs 24 hours a day, 365 days a year. The Internet is usually referred to as the net. The Net is a general purpose, international communication an information system. How can you take advantage of Internet?Internet is a vast treasure for
History of the InternetHow was Internet started? Some time Internet the 1960's the US Department of Defense started a project called ARPANET. The objective of this was to connect a large number of computer facilities. The most important feature being that if one part of the net get destroyed the rest of the network would still function. How does the net function even if the communication lines stop working temporarily?The computers that run the Internet automatically reroute the flow of information around the broken links until they start working again. When a communication line stops working, we say that the computer (or line) is Down. Similarly when Internet is working, we say it is UP. There is no way that the entire Net can be shut down. How does the Internet work?The Internet is based on a large number of client server programs, where the server acts an all the requests made by the client. When you are connected to the Internet, your browser will be the client, and your ISP's computer will be hosting a server program. This server will make sure that you get to see all the requested pages/information, and all other requested tasks done. This it might do itself, or get other servers to do the same. What is TCP/IP (pronounced as T-C-P-I-P)?Just as human beings have a language through which we communicate: programs on the Internet (client and servers) communicate using protocols. All data on the Internet is transported as packets: The two most important protocols are the ones that provide the basic transport. IP (Internet Protocol) is used to move data packets from one place to another, while TCP (Transmission Control Protocol) manages the flow of packets and ensures the data arrives intact without errors. List of Important TCP/IP protocols
Note of Caution!Not everything is perfect on the Net. There are good people and there are bad people, there could be all kinds of legal and illegal stuff on the net. There could be stuff, which is offending. the Internet in its very real sense reflects life in general, with all the good, bad and ugly coexisting. If you don’t like something-ignore it!Internet can be accessed only when you are connected to the Internet. This for home users is usually done through a telephone line, by dialing to your chosen Internet Service Provider (ISP). This dialing may sometimes take a few minutes. Also, it is to be remembered that it will take more time to access information on the net than one takes to access files on their own system. Types of Internet ServicesInternet is normally accessed through a modem. Modem transmit data at different speeds. Different types of communication technologies are used for Internet access by consumers round the world. Why modem?Two means of communications are used - Analog and Digital. On the Internet all the computers and communication links are digital, except the link between you and the net. The signal that goes over the telephone line is analog, therefore the MODEM is used to convert the digital data (from inside your computer) to analog to make it capable of being transferred over the telephone line. Similarly, analog data is reconverted by the MODEM from analog to digital for use and understanding by your local computer. Definition of ModemThe process of converting digital data to analog data is called modulation and the vice versa process is called Demodulation. Thus the device which performs this function MODEM: Modulator/Demodulator. There are various ways to connect to an ISP, but remember: No connection can be too fast as the speed of your mind is faster than any connection. Speed is measured as to how much data is transmitted per second, i.e., Kilobit per second.(1 KB = 1024 bytes, 1 byte = 8 bits, 1 byte stores one character). Various ways to connect to an ISPEach type of connection requires a special modem, prices of which vary widely.
TopThe World Wide WebIn order to surf the web, you need to run a program/software. This program acts as a client to the various web servers and is called a Browser. Various kinds of browsers are available in the market. Internet Explorer provided by Microsoft, and Navigator are among the most popular. Popular Browsers in the market
These programshave a variety of settings for access. These settings generally control the operation of browser. Microsoft calls these Settings, while Netscape calls them Preferences. You can even change the appearance of the browser if you so want. A word of precaution, Original settings should be noted, in case you wish to restore the original settings. On the Web, you don't need to know everything. Use the help key F1 whenever required or call the helpdesk or a friend who may be able to help. Host names and top level DomainsOn the Internet every computer, every page and every source has its own address. These addresses or hostnames are unique. Each host name has two or more parts separated by dots. Hostnames are part of a system called DNS (Domain Name System) which allow allocation of a unique name to every computer on the Net. A domain is a set of hostnames that have the right most part of their names in common. For instances, all the hostnames that end .in belong to the .in (India) domain. For example: abc.in, wxy.in. When hostnames have the right most part of their name in common, we say that they belong to the same second level domain. The right most part (.in above) is called the top level domain. There are two types of top level domains:
Organisational domains represent a particular category, while the latter a particular country. www.xyz.in, would indicate an Indian site as ".in" stands for India. Organisational top level domains
IP Addresses Hostnames are unique names we use to identify computers as they are easy to remember. However, computer programs find it easier to deal with numbers rather than names. Therefore, every computer on Net is given a unique number, the IP number/addresses. DNS The DNS server translates hostnames into IP addresses/number. However this system does not maintain a long list of all IP addresses and Hostnames. But Net architecture distributes the management of various domains. Whenever a program needs to translate a hostname into IP addresses, all that a program has to do is find the name sever that handles that domain. Each of these servers maintain a list of other name servers that handle the second level domain and so on. How does it work?Suppose you decide to visit a website called www.hotmail.com, the browser on your computer will send a request to your ISP DNS. This in turn will contact the root name server and will get the name of the COM named server. The DNS server then contacts the COM server and gets the IP address of hotmail i.e. 209.185.130.52. This information is then sent to your browser, which can then contact the web server directly. The Browser's Time Management SkillsTo save time and bandwidth most DNS systems keep a list of most frequently used addresses. Thus any subsequent request to the server will be serviced faster.
TopURL-Uniform Resource LocatorsThis is the unique address that helps the browser locate the unique server that hosts the website. URLs usually are of the following form: These are also referred to as web addresses. To enter a URL, use our mouse and click anywhere on the address bar and then type the URL. Another way to enter the URL is to press Ctrl-O, then type the URL and press enter. The above URLs are usually not case sensitive, however, some of these can be case sensitive. How does it work?When you type in a given URL, the browsers would first try and locate the address you have typed. However, if the address given is incomplete, it will try and complete the address by adding a .com to it, and search it again. If However, it does not still find the same, the message "the page cannot be displayed" appears. Reading a web pageMoving up and down a web page is usually simple, you can do it with your arrow keys or scroll buttons on the right of your screen. The scroll bar would appear only if the full page is not visible on your screen. What to do if a URL does not work?If the error message displays- "File not found" or "There was no response" or "Cannot open the Internet site". Check the spelling carefully. Many URLs are complex and it is easy to make a mistake. If the address is correct, then the problem may lie with your connection, to make sure that your connection is working-try sites like: www.microsoft.com
If the above do not work, then your connection has a problem. Call our helpdesk numbers. Saving URLs for future useURLs can be saved clicking on "Add to Favourites" in Internet Explorer, or "Add Bookmark" option in Netscape. Sending a URL or a web page to someoneInternet Explorer Click on mail button -"Send a link". Or on the file menu select "Send" and "Link By E-mail". Or right click and select the relevant option. Netscape File menu and select "Send Page" or right click and select "Send page" Setting a URL as your home pageEach time the browser is started this site will be started. Internet Explorer - pull down the view menu select "Internet Options" and the general tab. Within Netscape- pull the EDIT menu and select Preferences. In the Category Box, click on "Navigator". Clicking on the home button near the top of the browser window whenever you wish to come back to the home site. Buttons/ThumbnailsThese provide links to other web sites or pages with relevant information and further links, if any. These can be recognised by underlined text in different colours, or the mouse pointer would turn into a thumbnail symbol when it comes to such a link. Blocking AdvertisementsThis can be done by telling your browser not to load graphics automatically. In the Internet Explorer View menu select "Internet Options". Click on the "Advanced" tab, go down to the multimedia section, and uncheck the box next to "Show Pictures". In Netscape, Edit menu and Select "Preferences". In the Category Box, on the Advanced Tab, click on "Automatically load images". In case you wish to see a certain picture - then right click and click on "Show picture" (Internet Explorer) or "Show Image" (Netscape). Advertisement blocking software is also available, at a cost at: http://www.atguard.com CookiesA Cookie is data by a remote web server and stored in a file on your computer or browser. Cookies can be used to store any kind of data, but they are usually small in size about 4K. They are usually used to track your identity, your preferences and your actions as you navigate the web. They are often used to make your navigation of the web easier, through not always. Cookies can be deleted in the normal manner. A message warning you against the same may be displayed. However, deleting them will cause no harm. Whenever required new cookies will be created. Controlling CookiesInternet Explorer On view menu, select Internet Options and click on the Advanced tab. Scroll down the security section and look for cookie settings. Cookies can be deleted in the folder c:\windows\cookies.Internet Explorer Cookies would not be deleted even if you clean out cache using Internet Explorer, you will need to delete them yourself. Netscape On the EDIT menu, select preferences, and in the category box click on Advanced. Cookie settings will then be available for review. Cookie files are available in Netscape - directory\users\default\cookies.txt. ChannelsWhen you enter the URL of a page, your browser contacts the relevant server and request the page information. However, certain types of servers can send data to your computer automatically. Channels are useful, when certain information needs to be updated on a regular basis. Channels are the same as web pages, which like television - you can go to the channels to see what's new. The systems that supports channels is called PUSH, and you run a PUSH client on your computer. The PUSH clients available within the Internet Explorer are called Active Channels. Netscape's PUSH client is called NETCASTER. However, this is a separate program, which might need to be downloaded. The PUSH client updates channels periodically as scheduled, or you can update the same manually. Once the channels is updated, it can be accessed without being connected to the Net. Thus you can carry updated versions on a laptop, and view them at leisure. How to get the information deliveredSign up with a broadcasting service by subscribing to web pages in Netscape or Internet Explorer and have pages downloaded to your computer. Use a channel viewer to see websites that are set up to deliver updated information. Sign up with Mind-It (or similar) website. This website http://mindit.netmind.com, asks for you e-mail address and URL of a web page. Whenever the web page changes, Mind-IT sends you the updated page by e-mail. Channels can be configured as per your preferences, this could be scheduling updates, or levels of updating as to number of pages, adding or deleting channels. Some websites also have an ADD to channels list tab, which can be clicked and the websites automatically gets added to your channels. Search enginesThis is a program, which can search a large database for specific information. On the web, there are many such engines, which keep track of everything on the web, and these are available for free. Some of the search engines are: www.yahoo.com Various portal sites also offer effective search engines. Techniques of using a search engine:You need to type in the key words, which you expect to be present on a website relating to your search. For example if you wish to find information about Jawahar Lal Nehru and his contribution to the freedom struggle- you wish need to enter "Jawahar Lal Nehru " + "freedom struggle" + "India". This will return you the links to all web sites found containing the above words. However if you write only "freedom struggle", then you would get web sites giving details of all web sites including the freedom struggle of Namibia. And if you simply use freedom struggle without the double quotes, you might would be given links to all sites which mention freedom or struggle anywhere on their page, which could also be a stop cruelty to animals site. Using Operands Operands like + (the plus sign),-(the minus sign)and " " (the double quotes), so that the words given within quotes are searched for the perfect match for characters within the quotes. Some search engines also use the Boolean operands "AND", "OR" and "NOT" to be necessarily typed in capitals among the search key operands. Using wild cards Another search trick is wherever you type the URL, you can enter a ? (question mark character), and follow it with a list of search words. On pressing enter, the browser will atomatically submit the search words to a search words engine and display the results. E-mail provides a good, cheap and quick communication medium to all users. E-mail messages are transferred using a protocol called Simple Mail Transfer Protocol. SMTP is understood by all e-mail applications that package your Internet e-mail message for sending and by all computers, servers that pass the message along the route. Mail servers receive and store e-mail messages in mailboxes by using a protocol called Post Office Protocol(POP) or POP3(since they cuuent version of POP is version 3. Mail servers are sometimes also called POP servers. To read your e-mail, you need an e-mail application (also called a mail client or POP client) such as Outlook Express, Netscape's Messanger or Eudora. Downloading E-mailYour e-mail client downloads mail from the POP server. However, you can usually work either off-line or on-line. You can choose to either leave downloaded messages on the server or delete them from the server. E-mail formatsE-mail can be received in plain text format or in HTML, Rich Text, MIME, Microsoft Word format. Not all e-mail progrms can read all format. Therefore it is advisable to use to send mail in plain text format, unless you are very sure that the receiver would be able to read your mail in the particular format. Signatures and StationaryA small signature file can be created and this can be identified on Tools menu and select "Stationery". Click on ,ail tab and then on the signature button. Within Netscape Messenger, on the Edit menu select Preferences and in the category box, click on "identity" under Mail & Groups and then specify the name of the signature file in the appropriate box. FiltersFilters allow you to process incoming mail automatically in various ways. You can create as many filters as you want. IN Microsoft Outlook Express, in the Mail Window Tools menu select "Inbox Assistant". To create new filter, click on Add button. In Netscape Messenger, go to the Message Center window, in the EDIT menu and select "Mail Filters". To create a new filter, click on the New button. SpammingSpam is advertising that is sent to your e-mail address without your permission. To block this mail you can simply use mail filters and block senders. Encryption and SecurityThis is possible using a digital ID or certificate. With Microsoft Outlook Express, pull down the tools menu and select "Options". Click on the security tab, and then click on "Get Digital ID". With Netscape Messenger, go top the Message Center. Then pull Down the Communicator menu and select "Security Info". Click on "Ours" (under "Certificates") and then click on "get a Certificate". E-mail netiquetteNetiquette is the term used for the etiquette on the Internet.
Ways to keep Mail address Private
WebmailWeb based mail can be accessed from any computer on the Net, anywhere in the world. It is useful and usually free. They derive their revenue from all the advertisements that they put on the page while you access your e-mail. Select your own web based mail, keeping in mind the following:
The following provide good free web based mail services:
Webmail may be less secure than using a POP e-mail client, mainly because someone can click on the back button of your browser and read your mail. Someone can read your mail stored in the cache. Thus while using web based mail, be sure that you empty the browser cache and close the browser after using the e-mail package. Netiquette-Commonly used Net SlangDon't type in capitals, it is considered equivalent to shouting. When you sign out of a chat room or a conference, say bye. Don't send frivolous messages.
TopChatThe term real-time refers to process in which you sense and response to something as it is happening. On the Internet such realtime communication, which carries typed messages back and forth, is termed as Chatting (even though you are not verbally communicating. Two kinds of talk/Chat facilities are availableWeb chat rooms is one in which the message is typed on a system, it then goes to a server and is then mode available to all the site to view and respond to. There is always somebody to talk to here, with thousands of different conversations. Direct connection is established through a resident program called a talk client on your PC. As you type, words are sent, to the persons talk client, without going to a central server. You are connected to only a few people and have more privacy and control over the environment. Web Chat Rooms This is a talk facility offered by a web site and supports a multi -person conversation. Some are set up for general conversation, others are devoted to particular topics or groups of people. Using a web chat room is easy, as you do not need to install a special program for the same. Most web chat rooms use only plain text, however, some may create artificial environments as you talk. You can move from one place to another. In such a system a small picture or figure moves and talks on your behalf. These figures are called Avtaar, because they represent you in your web Avtaar. Web chat rooms available:- http://chat.yahoo.com Avtaar based chat rooms: http://www.net-world.com Direct Connections These are faster than web chat rooms. For this you need to download install a chat client on your computer. These talk clients not only send and receive messages, but also perform a variety of other operations, which could prove useful. File transfer You can send files from our computer to the other person's computer, This might be easier than sending the file as an e-mail attachment. Web browsing You can send files from you computer to the other person's browser and can be handy when you want to show someone specific websites while you talk. The client chat program also lets the server know that you are on-line. The server keeps track of all the people on-line. The talk client can therefore tell you which of your chat friends or buddies are on-line. ICQThis facility is called instant messaging. ICQ (is a pun on, "I seek you"), is one of the most popular facility. The talk client for the same can be downloaded from: IRCThis is one of the largest Internet talk systems. It has grown enormously sine 1988. There are a lot of channels or topics available on which you can chat simultaneously. You can either LEAVE or JOIN a channel whenever you wish. Private conversations are also possible on IRC. IRC clients can be downloaded from: http://www.mirc.com/ Help information on IRC is viable at : www.irchelp.org/ MUDSThese are elaborate text based imaginary environment used for talking. It offers detailed environment, but since they are based, no picture, only text describes what you see. One can have adventures, explore exotic places, solve puzzles, take part in group events or a wedding. There are MUD villages, houses and towns. This is a role playing fantasy environment, where each person becomes a character. Participating in a MUD is a long term experience. Every Mud has regular users, who form a large extended family. MUD was earlier defined as Multi User Dimension, however, now it had become a word by itself. There are two types of Muds - social and adventure Muds For Muds like most other web applications, you need to download a Mud client: Mud client can be downloaded from: http://www.chaco.com/pueblo Mud FAQs & tutorials: http://www,faqs.org/faqs/games.mud-faq/part1/ Downloading Software from the NetThe net is the best source of free software, games , graphics, fonts, sounds, videos, etc. Downloading is easy, though there can be variations in the process of downloading depending on the type of system you use. Downloading is a five-step process:
Downloads can be found at : Help on downloading is also available on the same website. Plug-InsA plug-in is a piece of software that extends the functionality and capabilities of your browser. Most plug-ins are downloadable, free of charge and can be installed very easily. Instructions for downloading and installing the plug-in are usually available. To address the large size of audio and video files, streaming was invented. It enables play while your computer waits for the rest of the files arrives. Several streaming formats are widely used on the Web and you can install plug-ins and ActiveX controls to enable your browser to play them. Among this the most popular is REAL PLAYER< which can be downloaded from http://www.real.com. Playing MP3 musicMPEG3 or MP3 is a highly compressed audio format that is used for storing data, mainly music. Many music files are available on the NET in MP3 format, with a .mp3 extension. This is becoming extremely popular these days. You can also convert songs from CDs to MP3 format, though not all drives can be used to create MP3 files: the drive must be able to read raw data from music CDs. To play on MP3 format, you need a MP3 player, which can be downloaded from http://www.mp3.com List of plug-insStreaming audio/video plug-ins http://www.microsoft.com/ntserver/netshow/download.htm Multimedia plug-inshttp://www.apple.com/quicktime/download/ Music plug-inshttp://www.liveupdate.com/dl.html Look for more plug-ins athttp://cws.internet.com/32plugin.html Children on the NetThe web being a family resource, a lot is available for people from all walks of life. Children can interact with other kids an experts in the interest areas. Kids search engines are available. http://www.yahooligans.com are a few web sites for kids. The Internet Public Library, www.ipl.org is one of the best sites for starting any investigation or research project. Other websites for kids:
The Internet has a wide variety of sites available. Home computers are used by all but mostly by children. The Internet is a good entertainment as well as learning tool for kids. It may however, be desirable to block a child's access to certain sites. Site blocking services are available both on the Net, as well as your browser. Netwatch and Content Advisor are free components of Navigator and Internet Explorer. Two rating systems called SafeSurf and Recreational Software Advisory Council (RSAC) are built into Netscape Netwatch. Microsoft's Content Advisor includes only RSAC's system. More about the organisations can be found at: http://www.safesurf.com You can use more than one rating system simultaneously. However, not all sites are rated. Thus, the above may not really protect all access. www.getnetwise.org will provide more information on content rating software and other access restricting software. Other sites like http://www.indiaparenting.com provide guidance and advice on parenting. PC vs. Set-top boxesWhat exactly are the TV top Internet Boxes?The Television top Internet boxes are low priced, stripped down PC's which fit on top of your TV set. These boxes allow access the Internet, and display WEB pages on your television screen. To get the price down, older 386, or 486 technology, may be used. Components such as disk drives or CD ROMs are usually left out, or offered as accessories. The TV Top Internet Boxes also contain a modem, which connects to your telephone line. They usually have a remote control and offer a wireless keyboard as an option. Can I download any shareware or free software with my TV top box?The answer is usually no. The TV boxes are not a regular PC. With Couch Surfer, You still can use your computer as usual. Can I still use my TV like I'm Doing now?The answer is yes. Most TV sets have multiple input sources, Which are controlled with the TV's remote control. Can I use all of my PC software and view it on the TV?Some tasks are best suited (such as word processing) to sitting at a regular desk. You can try running other software with the remote keyboard and mouse, but you may find it best to use your PC as usual. Do TV Top Boxes allow me to use all of the Internet's resources?The ones we have seen do not. What the TV top browsers are showing you are basically just a part of the Internet, web pages and E-mail. There are a lot of other similar devices, which will appear in the market in the near future, but for right now PC is the best Home Internet Access Device, which we have. |
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