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Joe St Sauver, Ph.D.
Director, User Services and Network Applications
joe@uoregon.edu
In talking with users, we know that while many folks are able to "click around" and eventually get where they need to go on the World Wide Web, they may still be confused about web addresses (also known as "URLs") and how browsers work with them. This article is intended to clear up some common questions and help you use your browser more efficiently.
Your web browser comes preconfigured to start at a default website, usually the browser creator’s own "portal" site. Most of these sites aren’t bad, but since you have a choice, you may want to set your default home page to any web page you like, such as:
Below are instructions on how to change your home page setting, according to the browser you’re using:
Mac OS X Mozilla: Go to the Mozilla menu and select Preferences... Click on Navigator. Enter your preferred home page in the Location: box. Click OK.
Windows Mozilla: Go to the Edit menu and select Preferences... Click on Navigator. Enter your preferred home page in the Location: box. Click OK.
Mac OS X Internet Explorer: Go to the Explorer menu and select Preferences... Click on Web Browser. Enter your preferred home page in the Address: box. Click OK.
Windows Internet Explorer: Go to the Tools menu and select Internet Options... On the General tab put your preferred home page in the box. Click OK.
Although it’s common practice to begin web journeys by using a search engine, there are times you will already know exactly what site you want to visit. If so, there’s no need to search for anything, you can just go directly to that site.
To do so, simply type that web address into your browser’s address bar and hit return. Your web browser will then immediately take you to that address. Note that your browser’s address bar is near the very top of the browser screen—it is not the search box that most portal pages prominently feature.
In the sample browser window shown below, the top arrow is pointing to the browser’s address bar (you can directly enter known website addresses here):
This is a portal page search engine box. If you already know the complete web address of a site you want to go to, you do not need to bother searching for it here! Simply enter the address in the browser address bar ("Search the Web:" window shown above).
It is certainly true that many web sites have addresses that begin with "www," but many others may not. For example:
| Site | Address |
| UO's password-changing website | http://password.uoregon.edu (not http://www.password.uoregon.edu) |
| Slashdot, a popular site for technical news | http://slashdot.org/ (not http://www.slashdot.org) |
In some cases, sites with perfectly good three-part addresses have become so resigned to users habitually using the www prefix that they’ve simply defined an additional address that includes www at the beginning of the address. However, we do not recommend that sites do this—it just adds to the confusion rather than eliminating a problem.
Because most commercial websites end in ".com" it is easy to make the unwarranted assumption that every web address has that suffix. Many web addresses do end in ".com," but many others do not.
Consider, for example, http://www.uoregon.edu/ (our domain ends in .edu because we’re an educational site), http://www.whitehouse.gov/ (the .gov domain is for US government entities), or http://www.bbc.co.uk/ (the British Broadcasting Corporation’s website in the United Kingdom).
If you forget to mind your .edu’s, .gov’s, or other URL endings, you can end up in some unexpected (and occasionally unsavory) online neighborhoods.
While .com, .net, .org, .gov, .mil and .edu are probably the most commonly seen domains at the University of Oregon, you may see other "exotic" domains such as .de (Deutschland, better known to Americans as Germany), .ch (Cantons of Helvetica, aka Switzerland) or .za (Zud Afrika, aka South Africa).
For a complete list of domain name country codes, including pointers to the whois servers that have registration information about domains, see http://www.iana.org/cctld/cctld-whois.htm
While you’re always okay entering a complete web address (such as http://www.uoregon.edu/index.html), you can usually get away with abbreviating web addresses quite a bit.
For example, most of the time you can safely omit the "http://" at the front of a web address. Thus, entering http://www.uoregon.edu/index.html or www.uoregon.edu/index.html will get you to the same location.
Likewise, if you just want the default top page for a website, you don’t need to explicitly specify the "index.html" part of the URL. Thus both http://www.uoregon.edu/index.html and http://www.uoregon.edu/ will get you to the same web page. You can also usually omit the trailing slash, but it is more efficient (at a technical and probably imperceptible level) if you remember to include it.
If you trim a web address further still, your browser will still try to make a good guess at the site you’re trying to reach. For example, if you enter just a single word as a web address, such as "darkwing," your browser will usually assume that you’re looking for darkwing <your default local domain>.
If you’re connecting from the UO campus network, or from a UO dialup modem, your default local domain will be uoregon.edu, and hence you’ll go to darkwing.uoregon.edu, which is probably what you intended.
However, if you’re connecting from a non-UO network, such as mindspring.com or attbi.com, for example, your default local domain will not be uoregon.edu, and your computer may assume you’re trying to go to darkwing.mindspring.com or darkwing.attbi.com by default, which is probably not what you meant. Specify the entire URL in that case.
The people who created your browser also knew that many of the most popular websites have home pages of the format www.<domain>.com Because of that fact, if you’re at the UO and you enter a single word as a web address, such as cnn, your browser will first look for cnn.uoregon.edu, and then try www.cnn.com(which is probably what you meant).
Can these rules cause problems sometimes? They certainly can. Consider the case of a national website known as www.darkwing.com, or a local website called cnn.uoregon.edu!
If these rules about abbreviated web addresses seem puzzling to you, don’t worry about it. When in doubt, you can always just enter a full web address and it will work fine.
If you see a URL that has a tilde in it, that’s a clue that the web page is user-maintained and located within a user’s personal web space. Web pages that are stored in a web server’s primary document directory will typically not have a ~ in their URL.
Why would this matter? Knowing whether a web page is an "official" web page or a user-maintained web page may help you assess the degree to which that web page may be considered "authoritative" or "official" or may give you important clues about where to direct comments about a web page that may need attention. For example, if you had a question about the web page http://darkwing.uoregon.edu/~xyz/ , you’d know to try writing to xyz@darkwing.uoregon.edu to ask for help with that page.
When we talk about all-numeric web addresses, we’re talking about URLs consisting simply of a "dotted quad," or a numeric address that might look like http://128.223.142.13/ —not a "symbolic" domain within .com or .net or wherever that just happens to include a number, such as http://www.411.com/
The first thing you should know about websites using raw numeric addresses is that using raw numeric addresses for websites is a really bad idea. If a web server needs to move from one network address to a new one and all you’ve got as an address for that server is its old numeric address, you’ve effectively "lost" that website.
On the other hand, if you are using a symbolic address for a server and that web server is relocated, everything will be back to normal as soon as the symbolic name for that server has been updated to reflect the new location.
So why do some sites use all-numeric addresses?
Some websites with just a numeric address may have intentionally not bothered to create a symbolic name for that address. For example, in some foreign countries that don’t use the roman alphabet (e.g., China, Russia, Greece, Thailand), there may be little perceived value in registering an English language domain name and hostname in an "alien" alphabet that will never be used by local customers.
In other cases, a user may not have authorization to register a host name or to run a web server, and may be using just a numeric address in the vain hope that will let them fly under the radar. (It usually won’t!)
Originally, normal web pages written using HTML (HyperText Markup Language) had names ending in .html, while preformatted plain text files (the online equivalent of a page of plain typewritten text) had file names ending with .txt
When your web browser would see a web page with an .html extension, it would "know" to expect a page that included HTML formatting instructions. Similarly, when your browser processed a URL ending with a .txt extension, it knew it could just display that file "as-written," that is, as a preformatted plain text file.
So how did .html become .htm? The .html extension was created as a matter of necessity for some systems that didn’t know how to handle file names with file extensions more than three characters long.
What about .cgi, .php, and .asp? Those file extensions all signify that you’re working with a "dynamic" web page, or a page that will usually accept information from you and return customized results. Examples of pages of this sort include online shopping carts used by e-businesses.
Most web pages are sent across the network unencrypted. That is, if someone were eavesdropping on your transmissions, they could see exactly what you were looking at, or see all the information you might be entering into an online order form. URLs that begin with https, however, are transmitted "encrypted," meaning that someone looking at an https file as it is transferred over the network would see nothing but gibberish. This is obviously a good thing for sensitive information such as usernames and passwords, credit card information, and so on.
Secure web pages also protect you against another potential problem: how can you be sure of the identity of a particular site? In the case of websites running with a certificate issued by a major certificate authority (such as Verisign), you can be quite confident that you’re not connecting to a fraudulent site that’s masquerading as a legitimate e-commerce destination. You should be wary, however, if you connect to a site that is using a "self-signed" certificate, or a certificate issued by a certificate authority that your browser doesn’t recognize! That site may be fine, but you can’t tell for sure.
One other thing we should mention: just because a website transits its pages securely using https doesn’t mean that the site as a whole is secure. Protecting network transmissions from interception is important, but doesn’t do a thing to protect you from other threats— such as a hacker/cracker breaking into a server that has your credit card number stored on its disks in plain text!