Web Searching

PAGE (2 of 10)

Types of Search Tools

Indexed Database Engines

Also known as robots, worms, spiders, wanderers or crawlers, indexed search engines automatically and routinely update their databases, gathering information through a program that wanders through the WWW searching websites and other internet resources it runs across.

Keyword Searches

• The most popular type of indexing is by keyword. Words and phrases are indexed in a search engine database based on location and frequency in a document.

  Full-Text Indexing

  Some indexed sites, like AltaVista, are full-text indexed. This means that every word in a document, (except for articles, conjunctions and the like), are indexed in the database.

  A search on a full-text indexed database is useful when you want to see all documents on a very specific word or phrase. However, you wouldn't wish to use it in a general subject search which could return a huge number of irrelevant hits.

Subject Directories (aka Human-Reviewed Sites)

In a subject directory, individuals review and index web pages in a database, selecting words and phrases to describe them. The content is usually organized into directories, with more general topics at the top level, working down to more specific topics. The results of a search may be highly relevant, but not as current as with indexed database engines due to time required by the reviewers.

Meta-Search Engines

Meta Search Engines employ several search engines in parallel. They accept a query, submit it to multiple, individual search engines, compile the results, eliminating duplicates and display the returned results. Meta Search sites tend to be slower than individual search engines and are best for fairly simple searches.