The effect of unnatural linking patterns on your search engine rankings

The effect of unnatural linking patterns on your search engine rankings Inbound links are one of the most important factors that Google uses to determine the position of a website in the search results.
Some years ago, it was sufficient to get a lot of inbound links to top Google's search results. Nowadays, it's not that easy. Google has started to detect unnatural linking patterns.
What are unnatural links?

Unnatural linking is linking that wouldn't happen if search engines didn't exist. Unnatural links are links that are built purely to increase the search engine rankings of a website. These links don't have topical relevancy.
For example, unnatural links are:
links from totally unrelated websites (that have no value to the web surfer)

links from blog comment spam and forum spam

links that exploit a weakness in server design (like form injection)

What are natural links?

Natural links are simply links that webmasters would also build if search engines didn't exist. For example, reciprocal links with related websites make sense (I send visitors to you and you send visitors to me, our visitors benefit from the links).
If a link is logical and on-topic then search engines will like the links. The following graphical example explains why on-topic links will increase your search engine rankings:

The topic of your website is symbolized by the green color. The more other "green" websites link to your site (symbolized by the green arrows), the deeper is the green of your own website.
In that case, search engines know that your website is very relevant for this "green" topic and they will give your site high search engine rankings for search terms related to that topic.
Now lets take a look at the effect of unrelated links:

The links from unrelated websites (symbolized by other colors) take away the green from your website. They make it harder for search engines to identify the topic of your site.
If you have a lot of links from unrelated web pages then your website becomes less relevant to the original topic of your site.

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