Connectopedia Online Web Directory

Daily we use Internet services and search tools in particular when seeking data. The search results are usually provided in the form of a list and are normally called hits. The data may consist of web pages, images, data and other types of files. Some search tools also gather data available in databanks or open directories. If compared with Internet directories which are maintained by human editors, search tools work automatically or are a mix of algorithmic and human input. Web search engines work by storing information about numerous web pages which they retrieve from the INTERNET. These pages are retrieved by An Internet crawler, or differently called a spider. It is an automated Web browser which follows every link it finds. After that the content of each page is analyzed to determine how it should be indexed. Words, for example, are extracted from titles, headings or special fields called meta tags. Data about web pages are stored in an index catalogue for further use in queries. Some search engines, such as Google, save and store the entire or part of the source page (known as a cache) as well as data about web pages, whereas others, such as AltaVista, save and store every word of every page they have found. The cached page always comprises the actual search text, because it is the one that was actually indexed. Therefore, it can be very useful when the content of the current page has been changed and the search terms are no longer in it. As soon as a user has typed search words in the search field, the engine checks its database and displays a listing of best-matching web pages according to its parameters, normally with a short summary combined with the title of the document and at times parts of the text. Some search tools have introduced an advanced feature called proximity search that allows users to determine the distance between search terms. The usefulness of a search engine depends on the relevancy of the result set it provides. Since there may be millions of web pages containing a particular word or phrase, web pages can be divided into relevant and irrelevant ones. The results can be ranked to display the "best" ones first. The way a search engine displays web pages varies from one engine to another. The techniques also alter in time, since the use of the Internet alters and new techniques emerge.