To find something in the Internet, users often refer to directories. However it cannot help to find some individual subjects interesting the user. In that case search engines come to the rescue.
It is required to you
- The personal computer with the connected Internet.
1. The principles of work of search engines are as follows. Many users fondly think that after introduction of a question the search engine literally begins to comb through the Internet. In fact, everything occurs absolutely in a different way.
2. The classical search engine consists of three main parts, namely a web spider, an indexer and a search algorithm and also assessment of results.
3. The web spider represents the special program which is started on the personal computer which is connected to the Internet. The main objective of this program is search on the Internet, that is among its registered pages and in all possible directions. Villages represent hyperlinks. Thus, the web spider moves on hyperlinks and downloads from them pages for the second component of the search engine, namely index base.
4. The indexer is the processor of pages which were downloaded a web spider. This program is engaged in extraction from pages of words. Also she puts them in already created search base, at the same time writing all links where any word was found. Such principle is used in the search engine.
5. The search algorithm is the main innovation of the search engine. The efficiency of the result received by search, that is speed and accuracy of what the user can find, first of all, will depend on it. Thus, it is possible to draw a conclusion that when the user entered a certain request, the answer is looked for by the search engine in index base, and results are displayed already by means of a search algorithm.
6. In order that the search engine worked effectively, important that all three of its components well worked. And work of each component is connected with various cunning rules and means which need to be adjusted constantly. So that the search engine worked effectively, it should have a bright and fast web spider, an effective algorithm for search and powerful index base.
7. The relevance is degree of the compliance obtained the document to the entered question. The search engine defines compliance degree, that is what of the issued pages on demand where the necessary line meets, will be most interesting and useful to the user. It distinguishes one search engine from another and defines e efficiency.