A backlink is hyperlink pointing to a page on your site from another website. They are a key method by which users can navigate to your website but are also a fundamental aspect of how search engine algorithms decide on which page to return for a given query. Google pioneered the concept of using backlinks as a metric to help rank websites in search results through PageRank. After years of updates, search engines can now assess the quality, type and relevance of a backlink and its associated influence on a website’s ability to rank in the SERPs.

Why are backlinks important for SEO?

The concept behind a backlink’s value for search engine optimisation is based upon the core (but now defunct) theory of PageRank. In essence, the more authoritative the link giving site, the more link juice that is passed via the backlink and therefore the more influence the link has on a site’s ranking. If that doesn’t make sense, think of a backlink as thumbs up from one website to another. The more links you have the more popular your website appears to be on the web. However, this theory needs to have discretion applied to it in order to prevent manipulation, which was occurring pre-2012. With the Penguin Update, Google addressed the growing issue of linkspam by penalising websites with suspicious backlink portfolios (the links pointing to their website) by looking at the relevance and quality of the link giving site. SEOs must therefore focus on the value that a backlink provides for users and the relevance of the link in order to sidestep any potential penalties from Google’s antarctic friend.

Website’s can gain backlinks through a number of methods, most notably link building and link earning. They are fundamental to the success of an search engine optimisation campaign. In theory if there were no links to your site (including submitting a Sitemap to the Search Console) then Google would have no way of navigating to your site and therefore it would not get indexed. Furthermore, research by Cyrus Shepherd at Moz shows that the likelihood of ranking for competitive search terms without any backlinks is very small. This coupled with the high profile Penguin Update has meant that backlinks are often the most talked about aspect of SEO, alongside content and keywords. Whilst they are undeniably important for the success of a website in the SERPs, they should not be the sole focus of a campaign.

Webmasters often focus on the quality of their own backlink portfolio, for good reason. However, there is evidence to show that placing a link on your site to other poor quality sites, otherwise known as ‘bad neighbourhoods’ can be detrimental to the trust allocated to your website by Google. As such, it is advisable to investigate the quality of any website that you are linked to and their subsequent backlink portfolio.

Backlinks are not only valuable from an SEO perspective. They also provide incredibly useful channels by which traffic can flow from another site to your website and are therefore useful components of an inbound marketing campaign. It is important to note though that for backlinks to be as effective as possible you should ensure that the destination page of any given backlink is as relevant as possible to the traffic that will be visiting your page. If they are directed to your homepage when a more specific page would be more relevant this will impact on their user experience and have a negative impact on your user and usage data. Relevance, quality and value are critical aspects to assess when looking to build or earn backlinks and indeed link out to any other website.