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Google's trump ---- PageRank

Within the past few years, Google has become the far most utilized search engine worldwide. A decisive factor therefore was, besides high performance and ease of use, the superior quality of search results compared to other search engines. This quality of search results is substantially based on PageRank, a sophisticated method to rank web documents.

PageRank is not simply based upon the total number of inbound links. The basic approach of PageRank is that a document is in fact considered the more important the more other documents link to it, but those inbound links do not count equally. First of all, a document ranks high in terms of PageRank, if other high ranking documents link to it. So, within the PageRank concept, the rank of a document is given by the rank of those documents which link to it. Their rank again is given by the rank of documents which link to them.

But it's not just links that matter -- the text included in the links is important too. Google assumes that this clickable text, known as anchor text, describes what the targeted site is about. For example, if links to a bookstore's site include the words "pop-up books" in anchor text, the bookstore's site will rank higher in searches for those terms.

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Created by Lan Man

Last Modified: Nov 11, 2002