How Links Affect SEO
If keyword is the word you hear most often with SEO, then links or linking is the word you hear
second-most often. Links are the foundation of topical communities, and as such they have as much,
if not more, weight with search engine crawlers than keywords do.A web page without links is like a desert island. It’s sitting there, right in the middle of the ocean,
but no one really knows it’s there. The island could be littered with diamonds. The plants that grow
on the island might heal every disease known to man. But if man doesn’t know the island is there,
none of that matters.It’s the same with your web site. It doesn’t matter how great the information or the products on the
site might be. If people can’t find it, it’s as good as a desert island.The purpose of links, then, is to first link your web site to others that are relevant to the information
included on your site. In addition, links provide a method by which traffic to your site is increased.
And isn’t that the reason you’re playing the SEO game? Your desire is to increase the traffic to your
site, which in turn increases the number of products that you sell, the number of sales leads you col-
lect, or the number of appointments that you set with highly qualified clients. In short, links lead to
increased profit and growth. So of course you’d want to use them on your site.Another reason links are so important is that links into your site from other web sites serve as “votes”
for the value of your site. The more links that lead to your site, the more weight a search engine
crawler will give the site, which in turn equates to a better search engine ranking, especially for
search engines like Google that use a quality ranking factor, like PageRank.Understanding Google’s PageRank
P
ageRank is a family of algorithms that assigns a numerical value to pages on the Web in an effort
to determine the relevance or importance of that page. PageRank, which was developed by
Google founders Larry Page and Sergey Brin, is proprietary to Google, but there are other search
engines that use a ranking system to help determine the order of search engine results. It’s interest-
ing to note that PageRank is named for Larry Page and doesn’t refer to the rank of the page.The exact algorithms that make up PageRank are not available to the general public. A version of the
algorithms that you’ll find here was filed with the patent for PageRank, but only Google knows every
variable that’s taken into account. It will help, however, if you understand how PageRank is calcu-
lated, so the following example (from Wikipedia.org) should help clarify those calculations.Simplified PageRank Algorithm
Assume a small universe of four web pages: A, B, C, and D. The initial approximation of PageRank
would be evenly divided between these four documents. Hence, each document would begin with
an estimated PageRank of 0.25.194
Part II SEO Strategies
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