Introduction to internet and world wide web (WWW)

February 23, 2010

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The Internet, in simplest terms, is a large group of millions of computers around the world that are all connected to one another. These computers are connected by phone lines, fiber optic lines, coaxial cable, satellites and wireless connections.

When you log on to the Internet you are given access to all the other computers that are connected around the world – although for some you need passwords.

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A Network is where 3 or more computers are connected to each other by phone lines, fiber optic lines, coaxial cable, satellites and wireless connections and can share information.

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• The Internet is a global network of networks.

• People and organizations connect into the Internet so they can access its massive store of shared information.

• The Internet is an inherently participative medium. Anybody can publish information or create new services.

• The Internet is a cooperative endeavor -- no organization is in charge of the internet.

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Three decades ago, the RAND Corporation struggled with possible ways for US authorities to successfully communicate after a nuclear war. Their chief concern was that any central network control center might be destroyed by an enemy missile. In a plan made public in 1964, the RAND Corporation proposed that the new network have no central authority.

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As of Jan. 2009, there were over 99 million hosts on the Internet.

Pop Est 2009 Internet Users %Africa 991,002,342 67,371,700 7%Asia 3,808,070,503 738,257,230 19%Europe 803,850,858 418,029,796 52%Middle East 202,687,005 57,425,046 28%North America 340,831,831 252,908,000 74%South America 586,662,468 179,031,479 31%Oceania 34,700,201 20,970,490 60%World Total 6,767,805,208 1,733,993,741 26%

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Computer (now increasingly phones!) Connection - Phone Line,

Cable, DSL, Wireless, ... Modem Network Software - TCP/IP Application Software - Web Browser,

Email, ... Internet Service Provider (ISP)

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Send and receive email messages. Download free software with FTP

(File Transfer Protocol).  Post your opinion to a Usenet

newsgroup. Yack it up on IRC (Internet Relay Chat). Surf the World Wide Web. And much, much more. There is no charge for most services.

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The Web was invented in 1991 by Tim Berners-Lee, consulting at CERN (European Organization for Nuclear Research) in Switzerland.

The Web is a distributed information system. The Web contains multimedia. Information in the Web is connected by

hyperlinks.

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A web page is a document on the World Wide Web.

A web browser is the computer program you use to retrieve and view web pages.

The most popular browsers are Microsoft Internet Explorer and Netscape Navigator.

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Web pages are stored in computers called web servers.

Any organization can setup a web server.

A web site is a collection of web pages. The starting point for a web site

sometimes is called a home page.

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Hyperlinks typically appear as highlighted (underlined and colored) phrases.

Your mouse cursor will turn to a "pointing finger" when you've found a hyperlink.

Click once to follow a hyperlink. Graphics can be hyperlinks.

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Your browser remembers where you've been.

Use the Back and Forward buttons to retrace your path.

Use the Home button to return to your start page.

Power Skill: Press and hold down on the Back or Forward buttons to see the list of web pages you visited.

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The uniform resource locator  (URL) is the unique identifier of a web page.

The location window displays the URL of the current page.

You can go directly to a web page if you know its URL: click once in the location window and type it in.

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Some sites use advertising to subsidize free content.

Most large web sites have some navigation scheme to find information.

Links on the home page will bring you directly to featured content.

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The logo animates during page load.

The progress bar illustrates page load progress.

The status bar displays page load status.

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The Stop button stops page loading.

The Reload button fetches a fresh copy of the page.

If the page is alreadyloaded, the Stop button freezes the animations.

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A bookmark marks your place on the Web.

Press the Bookmark button for its menu. Select "Add Bookmark” to create a

bookmark for the current page. Bookmarks stay on

the computer where you make them.

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Secure web pages use encryption to protect from eavesdroppers.

Secure web pages use https.

The lock icon closes on a secure page.

The privacy policy should tell you what the recipient will do with that information.

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That's everything you need to know to browse the Web.

Now, an even bigger challenge lies ahead: learning how to find the information you want.

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A web directory lists resources, organized by subject area.

PFMRD<www.pfmrd.org.kh> LookSmart <www.looksmart.com> Wikipedia <www.wikipedia.org> Job wanted <www.bongthom.com> Librarian's Index to the Internet

<www.lii.org>

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A search engine is a database of resources that can be searched by keywords.

Alta Vista <www.altavista.com> Northern Light

<www.northernlight.com> Google <www.google.com>

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Web Directory Search Engine

Easier to use. More resources.

Good for general subject searches or browsing.

Good for searches where you can use specific

keywords.

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Don't twist the mouse; make sure the tail points straight back.

Everything we do will use mouse button one -- the one under your index finger.

Most everything will be a single click. Do not move the mouse while clicking.

If you do, the computer will do something dumb, like turn the words purple, instead of what you want.

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Click the button to scroll one line.

Click in the trough to scroll a screenful.

Press and drag the slider to scroll continuously.

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Thank you for attending our class. Be sure to practice your new skills. Good luck!

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