Page Rank, Link Popularity And Link Reputation Are Tightly Related

Backlinks basically are developed when another website links to another using a hyperlink this will be used by the search engines to basically vote for your website. Unlike a democracy were the votes are all equal, the search engines believe some links count more than others, and this is basically what the PageRank algorithm determines by giving different webpages a score based on how much PageRank has been passed to them. Now i'm not going to bore you with all the details of the PageRank algorithm, partly because neither we or anyone outside of Google really knows!. Now in order to fully understand how to properly build a natural looking link portfolio you need to understand two important concepts, Link Popularity and Link Reputation. Link Popularity would be the sheer number of links you have pointing to your webpages. It could also be thought of as how much PageRank is being passed to your webpages. Link Reputation is what types of keywords were used in the anchor text.
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This is used to determine relevance for certain search terms in the search engine. So there are two struggles to be won. The first is to get as many highly valuable links as possible. And the second is to build relevance for the keyword phrases you are targeting. Now we don’t want to totally minimize the on-page SEO factor because it has its place, but you can make up for a lot of poor on-page SEO with excellent off-page SEO.