A search engine is a program that allows you to search for specific information on the web?
There are many search engines to choose from depending on what information you are looking for but some are better than others at locating particular information. These are the search engines considered by Search Engine Watch to be good choices to start with when searching for information.
Search engines use computer programs called spiders to trawl the web looking for new web pages to index. When you type a word or phrase into the search box of a search engine these words are checked against all the web pages the search engine has indexed. The search engine then produces a list of links, known as “hits”, which point to a page that the search engine thinks may be a match for what you’re looking for.
An advanced search offers
numerous options to make your searches more precise and obtain relevant
search results. With an advanced search you complete a form which
offers you a number of options for combining your search terms as well as
limiting your search in a number of ways such as by language, file
type or site. Many of the major search engines offer an advanced search
feature.
A site flavored search (such as the custom Google search offered from The Information Centre home page) returns results which relate the the orientation of the site which offers the search, eg an educational one in this case.
The invisible web is a term used to describe information that general search engines do not or can not index. Information that is of a transitory nature, such as newspapers and newswires; material from databases and government technical reports, are generally not indexed by search engines.
See The Invisible Web for a directory of some of the resources that the invisible web has to offer.