Astronomy Online

How to Search on the Web

Are you a newcomer to the World-Wide-Web and is Astronomy On-Line your first experience with this new, extremely powerful communication tool?

Or are you one of the WWW oldtimers who has become tired of surfing the Web without a goal and spending hours in front of the screen without any real purpose?

In both cases, you may be looking for some guidelines which will help you to use the WWW in an effective and systematic way!

This page contains information about the use of various Search Engines available on the Web.

Search Engines

Given the still rapidly growing dimension of the World Wide Web, finding information about one or more subjects may easily turn into a nightmare. Already in the very early days of the Web these needs were recognized and many mainly WWW-specialized firms and contributors have built software for Web-searching. These tools are called Search Engines and have become an indispensable part of the World Wide Web.

The basic principles of the various Search Engines are rather similar. They all have a query syntax for specifying the search string (for instance a word that represents the subject in which you are interested), and a huge database containing keywords, descriptions and Web URLs (addresses).

The keywords in the database have been extracted from keywords that can be included in every Web page. You may see these keywords in a HTML document by clicking the View button at the top (Netscape) and then on the Document Source.

After the query string is entered, the search software tries to find matches of the query string with the keywords in database. Having found one or more entries in the database, the search tools will return information concerning the Web pages found.

To speed up the search process, most of the tools offer the possibility to restrict the search to well defined areas of interest, e.g. music, computing, sports, etc. The Net Search button on the Netscape browsers list most of the search tools available on the net.

The Main Sites of World-Wide Search Engines

Below follows a small selection with some of the best known tools:

AltaVista (http://altavista.digital.com/)

Search service from Digital Equipment Corporation (DEC) that indexes more than 8 billion words from 30 million Web pages and 3 million articles from 14,000 Usenet newsgroups. The system is powered by DEC's Alpha RISC processor.

Lycos (http://www.lycos.com/)

Comprehensive Internet catalog that includes both subject and word searches. Includes a new email address search and Road Map, a service to give directions or a map. Search for text, graphics, sounds, and video.

Magellan (http://www.mckinley.com/)

Search engine and online guide to the Web with an extensive listing of rated and reviewed sites.

Yahoo! (http://www.yahoo.com/)

This pioneering Web guide, updated daily, is now integrated with AltaVista's search engine. A search of Yahoo! categories returns global Web search results as well. Includes My Yahoo!, a personalized information service.

Try it!

Why don't you try to search for information which may be useful for you? For instance, you may try to find information about your own city by typing in the name in the field reserved for the search. Then you will get an overview of the Web-sites which are available in your city, perhaps including your own! Or you may try ESO, but beware, you will find more than 20 pages of addresses on AltaVista!

Particularly useful astronomical Web-sites will be found in another area of Astronomy On-Line, under Useful Web Addresses.


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