In 1998, two graduate students at Stanford University, Larry Page and Sergey Brin, developed "Backrub", a search engine that relied on a mathematical algorithm to rate the prominence of web pages. The number calculated by the algorithm, PageRank, is a function of the quantity and strength of inbound links.[22] PageRank estimates the likelihood that a given page will be reached by a web user who randomly surfs the web, and follows links from one page to another. In effect, this means that some links are stronger than others, as a higher PageRank page is more likely to be reached by the random web surfer.
Back end tools, including Web analytic tools and HTML validators, provide data on a website and its visitors and allow the success of a website to be measured. They range from simple traffic counters to tools that work with log files and to more sophisticated tools that are based on page tagging (putting JavaScript or an image on a page to track actions). These tools can deliver conversion-related information. There are three major tools used by EBSCO: (a) log file analyzing tool: WebTrends by NetiQ; (b) tag-based analytic tool: WebSideStory's Hitbox; and (c) transaction-based tool: TeaLeaf RealiTea. Validators check the invisible parts of websites, highlighting potential problems and many usability issues and ensuring websites meet W3C code standards. Try to use more than one HTML validator or spider simulator because each one tests, highlights, and reports on slightly different aspects of your website.

Off page SEO: This type of SEO focuses on all of the activity that takes place "off the page" when looking to optimize your website. "What activity not on my own website could affect my ranking?" You might ask. The answer is inbound links, also known as backlinks. The number of publishers that link to you, and the relative "authority" of those publishers, affect how highly you rank for the keywords you care about. By networking with other publishers, writing guest posts on these websites (and linking back to your website), and generating external attention, you can earn the backlinks you need to move your website up on all the right SERPs.
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