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Understanding and decoding URLs
Uniform Resource Locators, or URLs, are the Internet addresses that you see on the Location bars at the top or bottom of your Web browser (e.g., Netscape or Internet Explorer). URLs provide a standard format for the transmission and reception of a wide variety of information types. Here is how they are constructed:
Every URL must have at least the first two elements shown above (the information directly before and after the //). Here are some examples:
Understanding the different elements of URLs will help you know what to expect before you click on a link. Also you will be able to ascertain what kind of organization or institution the information is coming from. In some cases, you may be able to reconstruct someone's e-mail address from a URL.The 1st part: Transfer protocol
The first part of the URL indicates what type of information is being transferred and, usually, what port (or "door") to the server is being accessed. Here are the most common types:
When you perform a simple yet elegant click of the mouse, your Web browser goes into high gear. It sends a message to a server, or computer where a Web site resides, asking it to send you information. The transfer protocol tells your computer and the server what formats of information need to be interpreted and with what particular features (e.g., I am using Netscape 4.7 or Internet Explorer 6.0). The servername.domain is the address of the server itself: your message has to go somewhere. Most server addresses have three parts:
Most servers have a name of some kind. It is a fallacy that all Web servers are called "www." Many are, but that is a simple matter of choice. Look at the URL of the document you are reading: you're looking at it on the Web, and there is no "www" in it's name. The domain is key to understanding where the information is coming from. Is it an educational institution, or is it a commercial service such as Prodigy? This is an important consideration when you are trying to evaluate an electronic document. Don't forget, the Internet is vanity publishing on its largest scale. This doesn't mean that documents coming from someone's personal commercial account are not valuable: it means that you have to apply your critical thinking skills.
Once you have been admitted to a server to get a document or "page", you need to know where you're going. Servers act just like your home computer: you keep your word-processing program in a separate directory from your modem software. In fact, your computer probably keeps the word processing documents in a separate subdirectory in the word-processing directory. Computers need to be neat and tidy in order to run efficiently. This is even more true when the computer is sending billions of bytes of information all over the world. The third part of the URL takes you directly to the directory and subdirectory where the page you want lives.
Now, there's a trick to some of this. Does the URL look like one of the following?
When you see a directory or subdirectory
The last part: Filename.filetype
The last part of the URL specifies the individual document you are looking at. If you go to the home page of any particular organization, there's a good chance that your URL doesn't include a file name. When you click on anything linking to that page, it probably will have one. Some standard file types include: