О. В. Фёдорова е. В. Мезина е. В. Хамис английский язык в сфере информационных технологий и коммуникаций учебное пособие

But not seldom happens so, that the list, given out by the machine, is very great and to see (overlook) it (him) simply not really. An output (exit) from this situation can become stricter selection of the information brought in the catalogue. One of most known such systems - catalogue Magellan to the address: http: // www.mckinley.com

This database contains the items of information on 80 thousand WWW-pages - that very much not much in comparison with those in millions, which exist in a network. However if Yahoo as the description of a resource uses one - two lines of the text, the employees of system Magellan on some of pages brought in their database, write the small reviews, and also estimate quality of these information resources on a five-mark scale. Till past bases of the reviews, Magellan owns as an own automatic index, for search in which it is necessary to throw the switch under a field of input in a rule (situation) entire database.

As a rule search represents one or several keywords divided (shared) by blanks.

The service, similar by the principles, of firm Point (http: // www.pointcom.com) in general basic emphasis does (makes) not on search, and on work with the thematic catalogue.

The service Point is known in a network for that its (her) employees are constantly engaged оцениванием of network resources and conduct the lists of those sites, which they consider (count) belong to “ to the best five percents(interests) WWW ”.

Firm Point conducts a shared database all “of five-percentage WWW-pages, where about everyone it is possible to read the detailed license.

The most old subject catalogue WWW is the catalogue Virtual Library:

http: // www.w3.org/hypertext/DataSources/bySubj ect/Overview.html

This system full enough covers a scientific layer WWW - servers of universities, laboratories and educational institutions.