Search Engine Rankings
Search engine rankings are determined by search engine algorithms. When search engine algorithms change, search engine rankings change. It is a well-known fact that Google and others are continually modifying their secretive search engine algorithms and thus their SERP rankings.
Some of these modifications have been so profound that listings of many websites disappeared from the SERPs literally overnight. Keeping track of web page or site rankings is one of the most common activities of any SEO practitioner. The driving force behind algorithm changes is almost always the following:
Improvements in search results quality
Penalization of signature search engine spam activities
Search engine algorithms are based on a system of positive and negative weights or ranking factors as designed by the search engine’s engineers or architects. One of Google’s search engine algorithms is called PageRank. You can view Google PageRank by installing the Google Toolbar. To quote Wikipedia:
PageRank is a link analysis algorithm that assigns a numerical weighting to each element of a hyperlinked set of documents, such as the World Wide Web, with the purpose of “measuring” its relative importance within the set. The algorithm may be applied to any collection of entities with reciprocal quotations and references. The numerical weight that it assigns to any given element E is also called the PageRank of E and denoted by PR(E).
The PageRank (or PR) is Google’s measurement of how important ...