Chapter 04. General information about Search systems (Google)

Google is the leader among search engines that occupies 60 % of the world market. Daily, about 50 million user’s requests are registered and more than 8 billion of pages are indexed.

Google has been created by the graduates of Stanford University Sergey Brin and Lari Pejdzhem. It was they, who applied the technology of ranging PR.  The count of the “authority” of the document is based on the information of the documents referred to it. A huge amount of the documents is referred, and the higher authority they have, the more authoritative becomes the document to which they refer. Quantitative value of the document or PR concerns to so-called static factors (they do not depend on concrete request) and taking this factor into consideration while defining the relevance of the document to the concrete request, as a weighting factor. For the definition of the document’s relevance, Google applied not only the text of this document, but also the text of the links which leads to it. The given technology allowed supplying with the relevant results to the answers on the user’s requests. Also Google occupies the leading positions as for such factor as satisfaction of the users with the results of their search.

Google makes a search among the documents in more than 35 languages including Russian. Nowadays many portals and specialized sites provide services of the information search in the Internet on the basis of Google, that makes the task of successful site positioning in Google more important. Google does reindexation in its search base approximately once per 4 weeks. During this updating, that is also called Google Dance, the updating of the base is made on the basis of information, which was collected by the robots during the time that past from the previous updating, and the recalculation of the PageRank documents volumes. Also there is a certain amount of documents with quite big volume PageRank, the information about which in the search base is updating daily, but the volume of the RageRank is recalculating only during Google dance.  You can find out the normalized RageRank volume for the concrete document, which was uploaded to the browser, having downloaded and installed Google ToolBar (http://www.google.com/toolbar/ff/index.html) that is a special toolbar for the work with this search system. Despite the fact that the search system has a form for the free page adding to the base, Google itself prefers finding new documents using the links from already known and it wouldn’t index the page, added through the form, if there would be no page, referring to it.