Accumulating relevant links from popular websites to yours is one of the many factors Google and other search engines use to rank your site.
For instance, I run a surf camp, and one of the reasons I've been able to get my site ranked on the first page of Google (without paying for it) is a strategy I use called "link baiting."
Link baiting is any tactic you use to get others to link to your site.
Because big-time players in the surf industry, such as Billabong and Surfline, link to my site, I've been able to get ranked at the top of Google for certain keywords I'm after. (Such as "Los Angeles Summer Camps," for instance).
All it takes is creating online content they (Billabong, Surfline and others) they find useful, then they will link to my site.
You can easily do the same by employing "link baiting" tactics. Here's a great article on what link bait is, and certain strategies you can use to get more inbound links to your website, too.