Browsing the Internet: An introduction
What do l need to know?
A browser is a program on your computer that enables you to search ("surf") and retrieve information on the WorldWideWeb (WWW), which is part of the Internet. The Web is simply a large number of computers linked together in a global network, that can be accessed using an address (URL, Uniform Resource Locator, e.g. http://www.veths.no for the Oslo Veterinary School), in the same way that you can phone anyone in the world given their telephone number.
URLs are often long and therefore easy to type incorrectly. They all begin with http://, and many (but not all) begin withhttp://www. In many cases the first part (http://, or even http://www.) can be omitted, and you will still be able to access the page. Try this with http://www.cnn.com.
URLs are constructed in a standard fashion. This may be of use to you. Take, for example, the address of this page:
http://oslovet.veths.no/teaching/internet/basics.html
The ".no" indicates that the server is in Norway. The page you have accessed is called basics.html, and it resides in a folder on the server called "internet", which is in the folder called "teaching". If the URL that you type does not work, and you have typed it correctly (no mistakes are allowed!), the reason may be that the host has renamed the web page, or moved it to another folder on the server, or you are not allowed access to that level.
Try removing the text of the URL stepwise from the right-hand end in this example, until you reach the main page:
http://www.bbc.co.uk/info/purpose/public_purposes/index.shtml.
It is possible, in many cases, to find your way back down through the hierarchy to the page you were interested in.
You don't need to know how the telephone network functions to be able to make a phone call. However, you ought to know how to use your telephone apparatus and the finesses (software) it contains. Your computer is the equivalent of the telephone, and a browser is the equivalent of the software that modern telephones contain. (A browser can also be used to handle electronic mail, create and edit information on the Internet, as l have done here, and to contact discussion groups. This presentation is limited to the use of browsers to surf the WorldWideWeb).
Searching the Web
If you don't know the telephone number of the person you wish to ring to, you need a telephone directory. The Web provides two methods of searching for pages providing information:
• sites presenting web pages sorted by category and subcategories, e.g. Yahoo (several sites, including http://www.yahoo.com and http://www.yahoo.no)
• sites offering search engines that return lists of web pages containing text that matches a search word or string, e.g. Google (http://www.google.com), AltaVista (http://www.altavista.com) and FAST Search (http://www.alltheweb.com).
Many web sites offer both, or a combination of, these alternatives.
Before you conduct a search, it is important to consider, among others, the following points:
1. Is your choice of search term is adequate, too restrictive or too general?
2. Is the search you have planned to undertake most suited for a search engine that categorizes web sites, so that you can browse through appropriate subcategories when the first results are returned?
3. Are you more interested in using a search engine that merely returns all the web pages it has found containing the search term?
4. Have you read the Search Help pages that most search pages offer? These will tell you how the search engine conducts the search, and therefore how you ought to plan your search.
5. Bear in mind the fact that engines differ in their coverage of the Internet, their speed and whether they are largely compiled manually by people or automatically by 'robots' that scan the Internet.
A search strategy must include knowledge of how the search engine you have planned to use handles Boolean Logic and other similar search terms, e.g.
• transgenic AND mice will find all pages covering transgenic mice, but not pages that only mention transgenic rats
• transgenic NOT mice will return pages on all species other than mice.
• "transgenic mice" will find pages that contain the phrase "transgenic mice", i.e. where the words are adjacent in the text, but will not return a page containing the text "transgenic rodents, including mice", for which transgenic NEAR mice would be necessary
• transgen* will return occurences of trangenesis, transgenic and transgenic (thereby increasing your chances of finding pages you are interested in), but will also return pages featuring the word 'transgender', which is probably not what you were looking for!
N.B. Not all search engines support all these options, some support many more, and all of them have a "default" function (e.g. AND or OR) which you must check before you start.
To illustrate the enormous implications that this may have for your search results, try out the following search strings in the AltaVista or Google search engines and note the number of web pages returned for each alternative:
• Karina Smith
• "Karina Smith"
• Karina and Smith
• KARINA and SMITH
• Karin* Smith
• Karin*Smith
Excellent reviews of these processes have been written by information specialist Krys Bottrill. These cover:
• Basic principles when searching the Web
• Choice of search terms and strategies
• Comparison of Search engines on the Web
Some websites about the Internet in general and animals in particular
These include:
The author of these two sites, veterinarian Ken Boschert, has published a book containing summaries of the most important links on these pages: "Mosby's Guide to the Internet".
While you are on the Internet, you can donate free food to the starving:http://www.thehungersite.com
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