Sunday, July 16, 2006

SEARCH ...SURF...BROWSE...

Photobucket - Video and Image Hosting
Maaf buat temen-temenyang mengunjungi blog ini

Blog ini masih dalam tahap perbaikan

Dalam waktu dua minggu kedepan akan ada perombakan besar2an :) akan diprivatisasi (menjadi BLOG PRIBADI)
awalnya mau GoPublik (Blog Tutorial) tapi blom ada ide yang orisinal


Search E n g i n e s

Collaborative filtering, huge database. Excellent. Natural language search engine.
Large database, good results. Search engine, vertical engines, directory.


Visual search tool.
Web, Usenet. Speedy. Large database. Search engine from Microsoft.
Web, Usenet. Directory. Large database. Search engine, includes pages of links.
Web, Usenet, news, maps, directory, yellow pages, company profiles. Metasearch tool. Site previews.
Search and directory, sports, news, weather, reviews. Deep Web metasearch tool.
Search and pictures, sound, news, software, rated sites. Performs metasearching on web, Usenet, FTP.
Web search and directory. Another metasearch tool.
Search engine with Google-style ranking. Clustering metasearch tool.
Search engine for university sites. Premier metasearch tool. Excellent.

D i r e c t o r i e

Most popular directory, image searches. Nicely set up directory from Reader's Digest.
Google rankings applied to Open Directory. Very Good. indocenter Indonesia Directories
Very nice directory plus search. Directory created by volunteer editors.
Directory of expert guides, including Web searching. Excellent, easy to use directory.
Very nice directory, dozens of categories Directory of sites by popularity. Also top 99 search engines.
Directory plus links to search engines. Shopping, information, news.
Directory plus search. Directory by educational subject, with annotated entries.
Really cool graphic directory with good reference links. Directory of education related sites.
100 most popular web sites in many categories, including newspapers. Engine with links to companies and government pages.
Directory. Good sections on Library and Education plus search.

R e f e r e n c e

Encyclopedia Britannica & Internet Guide. Search for Encyclopedia.
17,000 short articles (Concise Columbia Encyclopedia). Almanacs, Encyclopedia, Dictionary.
Concise version of Microsoft's Encarta. Reference and Library site.
Database of articles and reference materials. 20,000 biographies.
Another encyclopedia. Searchable book of quotations.
Excellent dictionary, multiple sources. More reference works. Good.
Links to facts, encyclopedias, dictionaries, news, much more. Dictionary of Computer Terms.
A global encyclopedia. Dictionaries and Thesauruses
Several hundred searchable dictionaries. The meanings of acronyms.
Extensive index of scholarly Internet resources. Wonderful list of specific links.
A list of lists, or directory of directories. Science sites.
Another dictionary. Search archived Web content.
Articles on philosophical topics. Community written encyclopedia.
Dictionary and resources.

D a t a b a s e s
The Invisible Web: Databases not accessible to ordinary search engines.

10,000 databases, archives, and search engines. Metasearch database categories plus other databases.
Powered by Intelliseek's InvisibleWeb, another flavor. Metasearch engine and 1500 specialty search engines.


Search hundreds of journals.
Hundreds of databases by category. Full text magazine articles.
Journals & other free academic content. Search engine for the invisible Web.
Companion site to Invisible Web book. Full text of more than 18,000 books.

G r a p h i c s

Search engine for photographs and graphics. Audio and film archive.
Image search from Google. Marine Art Information Center. Paintings, photographs, and more.
Art, photography, maps, and more. More than 100,000 art images.
Stock image photography. Thousands of art images.


Many excellent art works.
Search engine for graphics. The U. S. National Gallery of Art.
Links to all the arts, including museums. Links to hundreds of online maps from library at U Texas.
National Gallery of London. Encyclopedia of art and artworks.

S p e c i a l t y

Search discussion groups. Directory and search for health and medicine.
Lists of mailing lists, newsgroups, ftp sites. Search for retailers by category.
Directory of mailing lists, by category or search. Search for business info by company or industry.
Directory of people, business, government, cities, more. Ask real people questions.
Directories by AT&T of people, businesses, toll-free, more. Reference, news, diagnosis and other health info.
Find businesses, get maps and directions. Legal resources.
U. S. National Library of Medicine, Grateful Med. Yellow pages from everywhere.
Info on health, disease, nutrition, medicines. White & yellow pages, reverse phone lookup.

P e r i o d i c a l s

Links to 100,000 newspapers worldwide. Abstracts and some full text of 200+ journals.
Links to all media.




Keeps an eye on the news media.
News, book reviews. News and archives.

B o o k s









Lots of all type of books. All kinds of book information.
Search for the best price from many bookstores at once. Book information, reviews, sites with reviews.
Books, bargain books (remainders). ACQWeb's Directory of Book Reviews on the Web.
The University of California Library catalog. Books and other items.
Book shopping bot. Compare prices. Shopping bot to compare prices.

M e d i a

Internet Movie Database with reviews.
Online TV listings.
Radio and TV programming. Also Web directory.

N e w s
General News.
News source, search engine, and gateway to news sites.
liputan6.com
Links to SCTV News
metrotv news
Links to Metro TV Indonesia
Emphasis on technical and computer news.
Media watchdog organization.
Links to 15,000 newspapers, TV stations, other news sources.

Saturday, June 24, 2006

Using Internet Explorer 6

Using Internet Explorer 6

Internet Explorer is a Web browser produced by the Microsoft Corporation. This tutorial will cover the major features of version 6. For the sake of brevity, we will refer to the software as IE 6.

NOTE: Most of these features are also available on IE 5.5.

THE TOOLBARS

Toolbars

IE 6 has two toolbars at the top of of the browser window:

Menu Bar: Contains menu items that open up dropdown lists for related options. Among the items are options for printing, customizing IE 6, copying and pasting text, managing Favorites, and accessing Help.

Navigation Toolbar: Contains icons for a variety of features including navigating among Web pages, searching the Web using a selection of search tools, accessing and managing Favorites, viewing a History of visited pages, printing, and accessing email and newsgroups.

HOW TO ACCESS RESOURCES ON THE WEB WITH IE 6

1. If you have the URL (address) of a Web page

Type the URL to go directly to the page. IE 6 gives you two ways of doing this.

Type the URL in the Address bar at the top of the screen. To accomplish this, click on the Address bar to highlight the current URL. Then type in the new URL and press the Enter key.

Click on File/Open at the top left of the screen. A pop-up window will appear with a text entry window. Within that window, type the URL of the file you wish to retrieve. Press the Enter key.

2. If you are on a Web page

Click on:

- words or images which change the shape of the mouse pointer from an arrow to a hand and display a URL on the bottom of the screen when the mouse pointer is placed over it

- the blue words on the display screen

- the purple words on the display screen (the purple color indicates that the resource has been recently accessed on your terminal)

Note: The color blue is generally the default color for text that contains a link, and purple is the default color for text representing a link that has been visited in the recent past. Nowadays, Web page creators are coloring their links in all sorts of ways. The best way to figure out which text represents a link is to position your mouse over the words and see if the pointer shape changes from an arrow to a hand. The hand represents a link.

3. If you want to use pre-installed links

IE 6 offers a collection of Web sites in its Favorites collection. Click on Favorites on either the text bar or the tool bar at the top of the screen to access these resources.

NAVIGATING THE WEB WITH IE 6

IE 6 allows you to move back and forth among the Web pages that you visit during a session.

To go back to previous sites:

Click on the small Back left arrow on the navigation bar near the top left corner of your screen. Each time you click on this arrow, you will return to the next previous site that you visited. If you hold your mouse over the Back arrow, the title of the upcoming page will briefly appear.

To skip farther back, click on the small black triangle to the right of the word Back. This will bring up a list of pages you have visited. Click on any one of these choices to return to the desired page. This is the equivalent of clicking on the Back arrow several times.

Back

To move forward:

When you have returned to previous sites with the Back arrow, you can go forward again by clicking on the small right-pointing arrow next to the Back arrow. If you hold your mouse over this arrow, the title of the upcoming page will briefly appear.

To move farther ahead, click on the small black triangle to the right of the Forward arrow in the menu bar at the top of the screen. This presents a list of several sites you have visited. Click on any of the choices to return to the desired site. This is the equivalent of clicking on the Forward arrow several times.

Foward


ADDITIONAL TOOLBAR OPTIONS

Stop: The circle containing the X will stop a page while it is in the process of loading. This is useful if a page is not successfully or speedily retrieving.

Refresh: The square containing the two curved arrows re-retrieves the page you are currently viewing. This is useful if the page does not load successfully or completely.

Home: The home icon takes you back to the page that was on the screen when you first started IE 6. You can customize your selection.

Search: The search button opens up a function that uses one or more Web search tools. You can choose the search tool(s) you want as your default.

You can also customize your search experience. After clicking on Search, choose the Customize option and make your selection. A pop-up window called "Customize Search Settings" will appear. If you choose to "Use Search Assistant" broad search topics will be displayed and the appropriate search tool will be queried. You can also opt to have IE 6 remember your last 10 searches so that you can easily repeat them.

Also notice that you can click a button called "Autosearch settings." This allows you to choose the search tool you want when you use the Address bar as a search window. You can also customize this option on the "When searching" line. You can even choose to turn off the use of the Address bar as a search window. If you do this, all words you type into the Address bar will be interpreted as URLs.

Favorites: Favorites are Web sites you have visited that you would like to store for easy access. You can add, delete and organize your Favorites.

Favorites

To add the current Web page as a favorite, click on Favorites and then Add. To choose the folder where you want to store this listing, click on Create in and choose the folder you want. At this point, you also have the option to create a new folder.

To delete a Favorite, simply right click on the item and choose Delete. Or, you can choose Organize Favorites select the desired item, and click on the Delete button.

To move a favorite to another folder, click on Organize Favorites, select the desired item, and click on Move to folder. In the pop-up window, select the folder where you would like to store this listing.

History: The history function allows you to view and select Web pages you have recently visited. You can sort your items by clicking on the black triangle to the right of the word View. You can sort by size, date, the number of times visited, and the order you have visited today.

Mail: You can read email from this window. Choose the email software you wish to use by going back to the Menu Bar and choosing Tools/Internet Options/Programs.

Print: Allows you to print the current page.

Edit: You may edit the current page in the HTML editor of your choice. Choose the editor by going back to the Menu Bar and choosing Tools/Internet Options/Programs.

Discuss: You may set a default Usenet newsgroup server.


USEFUL OPTIONS ON THE MENU BAR

The menu bar at the top of the screen includes some useful options. Here are a few highlights.


File/New/Window: You can open up a second copy of IE 6 by using this feature. This allows you to visit more than one Web page at a time.

File/Edit with...: You can edit the current Web page using the editor of your choice. Select the editor by going back to the Menu Bar and choosing Tools/Internet Options/Programs. You choices will be determined by software installed on your computer.

Edit/Find (on This Page): IE 6 allows you to do a text search of the document on your screen. Choose this option and type in the word or phrase you wish to search.

Tools/Show Related Links: IE 6 will display pages that are related in content to the current page. This is a service of Alexa, a Web content and traffic analysis company.

The Tools menu offers you many ways to customize IE 6.

SAVING WEB DOCUMENTS FOR LATER USE:
HOW TO DOWNLOAD, EMAIL, AND PRINT

You can download to disk, email, or print the Web page on the IE 6 screen.

To DOWNLOAD

Click on File/Save As (top left of screen). A pop-up window will appear.

Save As

Save in: Choose the desired drive.

Save as type: Make sure you save the page to the file type that will be useful to you. If you save the page as a Web page, you will need a Web browser or HTML editor to view it. A text file (txt) can be viewed in a word processing program such a Word or WordPerfect.

Click on Save

To EMAIL

Click on File/Send (top left of screen).

You may send the current page as an email message, or you may insert the link to the current page within an email message. Once you make your selection, your email software will open. You can change the default software by going to the Menu Bar and choosing Tools/Internet Options/Programs. You choices will be determined by software installed on your computer.

To PRINT

To PRINT THE ENTIRE DOCUMENT

Click on the Print icon on the Tool Bar

Click on OK

To PRINT SELECTED PAGES

Print
  1. Click on File/Print Preview (top left of screen)
  2. Click through the pages using the navigation arrows and make a note of which pages you want to print
  3. Click on Print (top left of screen)
  4. Click on the circle next to "Pages"
  5. Type in the pages separate by commas, e.g., 1, 5-6, 7, 9
    OR, to print the page displayed in the Print Preview window, choose Current Page
  6. Click on OK.

To PRINT SELECTED PORTIONS OF A WEB PAGE



THE RIGHT MOUSE BUTTON

The right mouse button offers a number of useful features if you are using a PC. To view the possibilities, press down on the right mouse button and hold it. Options will display in a pop-up window.

The following is a selected list of right mouse button options.

1. WHEN THE MOUSE POINTER IS ON THE SCREEN (but not on a link or an image)

Right mouse pointer on screen

Selected options:

Back: Moves back to the previously visited page in your history list (same as Back icon)

Forward: Moves forward to the next page in your history list (same as Forward icon)

Select All: Selects all the text on the page for copying and pasting

Create Shortcut: Creates a shortcut to the current Web page on your desktop

Add to Favorites: Adds the current Web page to your Favorites

View Source: Brings up the HTML source code of the current page

Encoding: Allows you to choose a language

Print: Prints the current document

Refresh: Reloads the current page from the server

2. WHEN THE MOUSE POINTER IS OVER A LINK

Right mouse pointer over a link

Selected options:

Open: Opens the page

Open in New Window: Opens the link in a new copy of IE 6

Save Target As: Saves the link as a file

Print Target: Prints the link

Copy Shortcut: Copies the URL to the Clipboard for pasting into a text editor or word processing program

Add to Favorites: Adds the selected page to your Favorites

3. WHEN THE MOUSE POINTER IS OVER AN IMAGE

Right mouse pointer over an image

Selected options:

Save Picture As: Saves the image to a disk drive of your choice

E-mail Picture: Opens your default email program and attaches the image to the message

Print Picture: Prints the image on your default printer

Set as Background: Uses the image as your desktop wallpaper

Set as Desktop Item: Sets the image as an Active Desktop item

Copy: Copies the image to the Clipboard for pasting into a graphics editing program

Add to Favorites: Adds the selected images to your Favorites

CUSTOMIZING INTERNET EXPLORER

IE 6 offers a number of customization options. This section will highlight some of the more useful features available under Tools/Internet Options on the Menu Bar.

Tools/Internet Options is divided into six tabs. Each one is explained below.

Customizing options

1. General

Home Page: Specify the URL of the page you want to appear whenever you open IE 6, or whenever you click on the Home icon

Temporary Internet Files: This option allows you to view the files in your browser's cache. The cache holds viewed Web pages for subsequent quick viewing. Retrieving a file from the cache is much faster than repeated trips to the remote Web server where the file originated. You can customize the Settings to decide how often to check for newer pages, to specify how much disk space to reserve for your cache, and to view files in the cache.

History: This option customizes your access to pages you have visited with the History function. Here you can set the number of days to keep pages in your history.

Colors: Choose colors for links, visited links, and link hovers (the color appearing when your mouse is over a link). You can also set a default text and background color.

Fonts: Select the language script, the font displayed in Web pages, and the font displayed as plain text.

Languages: Select the language that will display Web pages accessed with IE 6.

Accessibility: Choose to ignore colors, font sizes and font styles on Web pages. You can also set a style sheet as the display template for all Web pages viewed with IE 6.

2. Security

Here you can set levels of security for individual Web pages. See IE 6's Help menus for more information.

3. Content

Content Advisor: You can enable ratings of objectional content to control the pages that may be viewed with this browser.

Certificates: This feature allows you to manage the identification certificates you may have. See the Help menus for more information.

Personal Information: This consists of two options. AutoComplete will store entered Web address, information entered into forms, and usernames and passwords needed to access sites you have visited. When you are using your browser, previous entries will come up as choices so that you don't have to retype the information. This can make your work go much faster. You can customize these options, and delete your settings. My Profile offers a template for enteringr personal information. If a Web site requests this information, you can give permission for it to be used.

4. Connections

Here you can store the information about your Internet Service Provider, configure your LAN settings, or send your browser requests through a proxy server.

5. Programs

Here you can set the programs you want the browser to use for HTML editing, email, Usenet news, collaboration ("Internet Call"), your calendar and contact list.

6. Advanced

This screen offers a number of options in the categories of accessibility, browsing, HTTP settings, Microsoft VM (Virtual Machine), multimedia access, printing, searching and security. Set these options if you are comfortable with them.

Friday, June 23, 2006

make money with internet

  1. If you don't already know it, learn some basic HTML. You have to do this to keep your costs down and still get what you want. Even if the site is basically laid out for you, you're going to need to know how to insert images, create hyperlinks, and do some basic text formatting. Our HTML Guide offers a free 10-week HTML class and a great collection of beginning HTML tutorials. Get over any anxiety you have about this. Just do it. You'll thank me for it later.
  2. Decide on your topic. You're going to be doing product reviews and recommendations, so pick a topic that you enjoy and know something about. If you can't stay passionate about the topic, that will show, and it also won't hold your interest. Choose a narrow enough niche to be distinctive, e.g., bands from your city, left-handed guitarists, music for a certain kind of dancing, authors of a certain religion, books about arts & crafts, etc.
  3. Choose your domain name. Make it keyword-rich, not clever. Think how people will find your site in the search engines. Here are some ideas (all available, by the way):
    Music: BandsFromTexas.com, BandOutOfBoston.com, SouthpawGuitarists.com, ClassicPsychedelia.com, Non-Stop-Hip-Hop.com, Merengue-Music.com
    Books: Mormon-Authors.com, Arts-and-Crafts-Books.com, Books-by-Stephen-King.com, ClassicBusinessBooks.com
    Others: Best-Baby-Toys.com, MomsMags.com, FelliniMovies.com
  4. Register your domain name. If you're not technically inclined at all, register your domain wherever you set up your hosting in step 5. Otherwise, you can save a few bucks by choosing a lower-cost provider. Not a big deal for one or two sites, but it can be for ten or twenty. I use GoDaddy, who have great domain management tools and are less than $10 a year. The least expensive I've found from a reputable source is 1&1, whose price is under $6 a year (last I checked).
  5. Set up your web hosting. This is where most people get burned. For this kind of site, you do not need $10 a month web hosting! Check out Discount-Hosting.com for no-frills hosting with adequate functionality and bandwidth, for around $10 a year! If you want more features, or especially if you're planning to run multiple sites, see GeekHosting.com or Multidomain-Hosting.com.
  6. Install weblog software. "Weblog, you say?" Yes. It will give your site all the structure you need, plus make it easy to quickly post new content. My pick is WordPress, which is open source (i.e., free), easy to install and use, and yet very powerful. Download it and follow their installation instructions. Turn on notifications to Weblogs.com and Blo.gs. In WordPress, this is under Options | RSS/RDF Feeds, Track-Ping-backs.
  7. Make it pretty. Free templates for WordPress are available at Not That Ugly. Choose a style you like and then tweak it to suit your tastes and the theme of your site.
  8. Set up categories. Most blog software allows you to create sub-categories to help organize your entries. This will help visitors narrow in even more specifically on their interests. For example, BandsFromTexas.com might have one group of categories for genre — rock, country, blues, etc. — and another for city of origin — Austin, Dallas, Houston, San Antonio, etc.
  9. Sign up as an Amazon Associate. It's simple and free. Just visit Amazon and click on the Join Associates link at the bottom of the page (here's a direct link for your convenience). Your site should already have at least the basic setup done, even if you don't have any content there yet.
  10. Create your blog posting bookmarks/links. There are two links that are going to be essential for you to make this easy. First is the blog posting link. In your blog software, on the posting page (see their instructions), at the bottom of the page there should be a "bookmarklet". Click on the link (and hold the mouse) and drag it up to your Links toolbar in your browser (assuming Internet Explorer), or your Favorites menu. This will allow you to blog a product with one mouse click.
  11. Create your Amazon Build-A-Link bookmark/link. This will make it easy to build the link with your affiliate ID built in. Log in to Associates Central, look in the left navigation sidebar, go to Build-A-Link, and under Static Links, find Individual Items. Click and drag this onto your Links toolbar or Favorites menu.
  12. Build your first link. Go to Amazon and find the product you want to review. Scroll down to Product Details and find the ASIN or ISBN. Double-click on the number itself to select it, then right-click and choose Copy. Click on your Amazon Build-A-Link link. Right-click in the search field and choose Paste. Change the selection from Served Link to You Host. Click Go. Your selection should show up. Click Get HTML. Choose the kind of link you want, select the highlighted text and copy it.
  13. Blog your review. Now click on your blog posting link (Press It! by default in WordPress). If you're using WordPress, you should now see two pieces of link code in your posting form, the first one ending with "Associates Build-A-Link >< /a >". Delete through that point. The second part is a link to the product with your Amazon Associate ID built in. Now just write your product review, choose the appropriate categories for it, and hit Publish.
  14. Build out your site. Before you promote your site, you want to have some substantial content there. Write several product reviews. Have at least 2-3 in each category you've created. You may also want to make a categories for articles, news, and commentary about your topic. The more content your site has, the better. And the great thing is that while you're writing all this, the search engines are getting notified automatically, assuming you turned on the notifications mentioned in step 6.
  15. Promote your site. The best free way to do this is to communicate with other bloggers writing about similar topics, and to participate in online communities where your topic is discussed. See the Online Business Networking category for ideas, as well as the Internet Marketing category.

Tips:

  1. You have to learn some basic HTML and basic concepts about running a web site. It's just not that hard. If you have to rely on purchased software, you won't be able to get exactly what you want, you won't know what to do when things go wrong, and you'll end up spending money you don't need to. Spend the time to learn it. It will be well worth the investment.
  2. I slightly recommend music over books and other products, mainly because you can listen to the clips of an entire album in about 10 minutes and get a good enough feel for it (without buying it) to do a short review. If you have another topic that you're passionate about, great, but make sure you have a unique angle on the topic. People can get reviews about a lot of those consumer products anywhere. You need to give them a reason to come to your site.
  3. To draw repeat visitors, create a newsletter. Frequency should depend on how often you're posting new content. Start with monthly. EZezine will let you send up to 1,000 messages a month for free, with no ads. By the time you exceed that, you should be able to justify paying for the service.
  4. To pick up some extra pennies, sign up for Google AdSense. It probably won't generate a lot of revenue, but it's free to sign up and completely effortless to maintain.
  5. Set reasonable expectations for earnings. You've only invested $20. You're going to make 5% on most products. That means that you need to sell $400 worth of stuff to make back your investment. To make $20 an hour, what you write must generate $400 worth of purchases. You get credit for other purchases made while at Amazon besides just the product you linked to, so it's not as hard as it may sound. It won't make you rich, but it's not hard to be profitable, and it builds over time.

Wednesday, June 21, 2006

internet (part1)

n

The Internet is a vast network of many different computers that are able to talk to each other in spite of the fact that they may be separated by large distances, may be very different computers built by different manufacturers, and may be running many different kinds of operating systems. This is similar to people in (say) Israel, Brazil, Japan, the United States, and Norway, each normally speaking a different language, being able to converse almost instantaneously with each other on very broad ranges of topics!

The computers of the Internet exchange packets of information using addresses that have much in common with ordinary mail addresses. These addresses are called Internet Protocol (IP) addresses.

How is such efficient communication possible? Well, there are two big advantages that the computers on the Internet have over our hypothetical natives of different cultures and countries. The first is that the computers of the Internet are in reasonably constant contact with each other over a set of telephone lines, transoceanic cables, satellite links, and so on that allow rapid transfer of electronic information. The second is that the computers of the Internet have agreed to a common set of understandings that allows them to exchange vast amounts of information even though internally they may speak very different computer languages.

These communications are possible because of a set of protocols, which is a fancy word for mutually agreed-upon rules about exactly how information will be transferred between the computers of the Internet. The two most important protocols that allow networks to cooperate with one another and exchange information are called TCP (Transmission Control Protocol) and IP (Internet Protocol). Collectively, these two protocols are often referred to as TCP/IP.

Local networks can be based on a variety of technologies, but as long as the software layers on top of the network hardware implement the TCP/IP protocol operations, a network can exchange intelligible information with the rest of the Internet.

How does information get transferred between computers on the Internet? A pretty good analogy is that of letters and the usual mail system (the one that computer types call "snail mail", because it is so slow compared with electronic mail!). The information is transferred in what are called electronic packets, which are something like letters containing information. If the packets are like letters, they must have an address. Just as normal letters must have an address on the front to make delivery likely, TCP/IP communication depends on addresses being included in each packet. Not surprisingly, these addresses are commonly termed "IP addresses". So, if someone asks what your IP address is, she is asking the electronic equivalent of what your post office address is.

As these packets of information move through the network, electronic devices called routers use these IP addresses to decide whether to keep a packet in a local network or to forward it to a different network. This is a complex task, because there are many networks that either comprise the Internet, or that are attached to it through some gateway.

Thus, routers and gateways in the network serve much the same function that different levels of post offices serve in the usual mail system, with each level of the postal system deciding whether the letter in question should be delivered locally, or forwarded to another part of the postal system.

The address on a normal letter typically has several lines, each of which supplies different levels of information about the exact location corresponding to the address. In a very similar way, addresses for Internet information packets have four fields that contain numbers and are separated by periods. For example,

222.36.28.37

is an IP address. However, people generally can remember names better than numbers, so it is convenient to associate a name with such an IP address. In this case, the corresponding name is

csep10.phys.upi.edu.

The translation between the numbers used by the network, and the name more commonly used by people is done by a computer called a nameserver. The purpose of a nameserver is to look up addresses, so its function may be likened to directory assistance on the telephone system.

If I specify csep10.phys.utk.edu as an IP address to a network, the first thing that it does is call its "directory assistance" - that is, a nameserver - to get the number associated with that name. (Actually, most computers have a small list of address-name mappings stored locally that they first consult, and only go to an external nameserver if they don't find the address there.) The network uses only the number, but by this method the humans and the computers are both kept happy: the computers in the network just have to deal with the numbers, which is what they do best, and the humans using the computers need only remember more symbolic names like

mycomputer.myplace.mynet.mycountry
which is what humans do better. Of course, the humans can also supply the IP address directly to the network as a number. Then, the nameserver isn't invoked. In fact, sometimes the nameservers, since they are machines, are down for some reason and one MUST supply the number to the network. However, that doesn't happen too often these days on modern and well maintained networks because there usually is more than one nameserver available, and if one is down another can often be found by the network when it needs a name translated

Let us consider as a typical example the internet address

www.techcorps.org

which is actually the name of the IP address 160.36.28.57. How did the people who run the Internet come up with that name, and how did we know that www.techcorps.org is really a nickname for 160.36.28.57?

The symbolic name of a site is determined by a naming standard known as the Domain Name System or DNS. Each field in a symbolic address corresponds to a single domain. The first field is a host name, which identifies a single computer. The last field is a top level domain. In between are things like department names, organization names, and so on in order of increasing generality.

For example, www.techcorps.org is the address for the main server of Tech Corps, which explains the ".techcorps" in the name, and this is an organization, which explains the ".org" part of the name. When we want to be precise we will term a sequence like 160.36.28.37 an IP address, while we will call the corresponding name csep10.phys.utk.edu the DNS name for the computer with IP address 160.36.28.37. However, in many instances we will use the term "IP address" to refer loosely to either the number or the name.

Some top level domains in the US and some sample addresses are listed in the preceding figure. Addresses of sites outside the US end with a two-letter country code; some common country codes are also listed in this figure.

f you wish, you may use this exercise to add links to your homepage that will aid in using electronic mail by providing ways to find addresses, and by providing on-line assistance for topics related to email. In the process, the exercise introduces the important technique of creating "lists" in HTML. In particular, you will see how to create numbered lists, where items in the list are numbered sequentially, and un-numbered lists, where items are not numbered, but each is preceded by a "bullet" symbol. You will also see how to "nest" one list as a sublist of another.