If you understand the history of Google, you know that link building will always be a part of their algorithm.
Years ago, before Google, search engines ranked websites purely on keywords. The more instances (or density) of a keyword, the better your page ranked. This is why people started adding white-colored keywords on white-background pages. This is also why their search results were crappy.
In this environment, Larry and Sergey created a new algorithm for searches. It was based on a simple analogy from High School. Who is the most popular kid in the High School? Not the kid that tells everyone they’re popular. The most popular kid is the one that everyone else says is the coolest.
You can apply this same lesson to life. Let’s say you go to your local Rotary Club and ask yourself, “which is the best plumber here?” It’s not the one who has “plumber” written everywhere on them: their hat, shirt, business card and truck. The best plumber is the one about whom the most people say, “THAT is the best plumber!”
Of course, it’s not just about the number of people testifying to your credibility. It’s about the quality of those people, and their expertise. Back to our plumber example: the best plumber is not the one with the most people vouching for them. The best plumber has the most credible people testifying to them.
Here’s a youtube video that explains this concept.
Where did I find this video? When I took Udacity’s CS101 class- building a search engine. Who co-sponsored this class? Sergey Brin. Yes, Google’s Sergey.
How did Larry and Sergey apply this concept of popularity to websites? Links. Links act as the votes for which web page is the best for a given topic. Links are the references for credibility, despite what someone says about themselves. Of course, a lot of links don’t make a site credible. Links from the best websites, make it credible. This is what makes Google a superior search engine. This is also why links will never go away, as a ranking factor and every SEO campaign will need to do some link building.
Of course, not all links help with ranking– but that doesn’t mean they aren’t valuable.