If the Internet is like an enormous globe and search engines are like atlases, links are the roads that connect the pages. But unlike your standard atlas, search engines use those links to see how pages are related to each other.
When it comes to SEO, links are even more important. For one, they act as a sort of popularity poll that helps rank sites. Search engines also use them to analyze site metrics like trust, spam and authority. Trusted sites tend to link to other trusted sites while less trustworthy sites usually have fewer sites willing to link to them.
While each search engine has its own unique algorithm for assigning value to links, there does appear to be some common factors, or signals, that help professional SEOs when they measure link values and profiles.
- Global popularity. Links from sites that have broad popularity also get more respect. For example, LinkedIn more than 2 million sites linking to it. Two earn trust from search engines, you’ll need to work with link partners.
- Local/topic-specific popularity. Essentially, a trusted site will be more popular with similar sites. For example, if you own an auto repair shop, a link from the Automotive Service Association will matter more than one from a garden society.
- Anchor text. If numerous links target a page with the right keywords, that page is more likely to rank highly for the targeted phrase in the anchor text, which is the visible, clickable text in a hyperlink.
- TrustRank. In order for engines to weed out spam (which accounts for most of the web), each one uses a system to measure trust. Links from trusted domains – such as universities, government agencies and non-profits – can boost your site’s trust.
- Link neighborhood. Your site is only as good as the company it keeps. If you link to spam, then you’ll be treated as spam yourself. Keep that in mind when you choose sites you link to, as well as when you seek links from other sites.
- Freshness. Link signals can go stale when they sag in popularity. It’s vital to keep earning new links so that your site will stay “fresh” in the search engines.
- Social sharing. Even though engines treat social media links differently from other links, they still notice them. Even though it’s unknown how much socially shared links matter in SEO, there’s no doubt that social media has a significant impact.