If you read anything about Search Engine Optimization, one item you’ll pick up very quickly is the need for link-backs to your website. Now, I think that’s a theory that intuitively makes sense to most people, but have you ever really thought about why they’re so important?
To fully understand why Google and other search engines consider them so valuable, you have to go back to the very essence of a link. A link is the highway of the Internet. Unless you know specific URLs (which is nearly impossible these days, domaintools.com shows over 125 million active domains) links are the only realistic way to get from place to place.
Not only are they the only real “transportation system” of the Internet, but they serve as one of the only “references” that search engines can read. So, when you link to someone else, and vice-versa, you are telling your customers/prospects that you personally endorse the other’s website.
That’s why Google rebukes companies so harshly for link farms and other forms of black hat SEO.
And that’s why links are so important in measuring a website’s quality score. It’s exactly due to these factors that it will likely be quite some time before Google or anyone else takes links down very far down in importance for search engine optimization.