The success of your Web Search depends on the level of your preparation. Before jumping to your favourite search site, spend some time and analyze your topic to determine exactly what you are looking for. Then, use the information given below to decide the kind of search system most suited to your needs. Finally use effective keywords and phrases that will enable you to get focused results.
The Web offers four general types of web search tools. These include search engines, subject directories, meta-search engines, and database resources. Each type of tool has its own strengths and uses. You will often find that using a combination of one or more of these tools helps your search significantly.
Search engines enable users to search for specific keywords and phrases within their databases.
The search engine database is a collection of Web pages that the search engine has "crawled" over. Search engines discover these web pages by using small software programs known as "robots", "spiders", or "crawlers". These programs visit Web pages and send the contents back to the main search engine for indexing.
The number of pages that search engines visit, and the number of times these engines visit a given page, vary across engines. Some of the best search engines may revisit Web pages every 20 to 30 days. The largest search engines claim to have indexed over 1.3 billion pages!
Search engines also vary considerably in the accuracy of the search results and the speed with which the results are returned.
The Open Learning Team has its own favorite list of search engines that you may find useful.
Subject directories enable users to search for web content in a manner similar to the index catalog systems in Libraries. Web sites maintained by subject directories are often divided into many category and sub-category levels. The search process usually involves starting at a broad category and then "drilling" down through the hierarchy until a specific topic of interest is found.
Unlike search engines, which rely on automatic programs to index web pages, subject directories are often compiled by human cataloguers who review and classify sites into the various categories the way a Librarian catalogues a library's resources.
Some subject directories also incorporate the keyword and phrase searching features of search engines while others actually use external search engines to provide users access to a much larger database.
We have put together a list of useful and popular subject directories for you to browse through.
Meta-search engines enable users to perform searches across a large number of search engines using a single search query.
Meta-search engines do not maintain a database of Web pages the way search engines do; instead they provide transparent access to many search engine databases, making it convenient for the user to search many different resources without having to search each one individually.
Some meta-search engines lump the results together as a merged list; others often group the results based on the original search engine that provided those results. Depending on your needs, both display styles can be useful.
Some of the most popular meta-search engines that we find useful are also listed on this site.
Web databases are often not searchable by search engines. They often provide valuable information and the careful Seeker must also consider these databases if only for the sake of being thorough.
Since search engines are not able to access the information in these databases, the only way to access the information is to actually visit and search the databases themselves.
The Open Learning Team has found the following invisible web databases to be quite useful.
The World Wide Web also provides us with many other specialized search tools. These tools are useful for finding images, graphics, videos, sounds, and other similar objects stored on the web. Many of these tools are directly part of larger engines, while others often just provide comprehensive resource lists that help direct the user to appropriate resources.
We have often found ourselves using the following additional search tools.