Link building is the process of building hyperlinks (or “backlinks”) to a website to improve search engine performance.

High-quality sites will naturally attract links over time. However, you may actively wish to solicit links from relevant sites to build a site’s authority more quickly.

Why is link-building important

Backlinks are the most important factor used by Google to evaluate a site’s authority. When reputable and relevant sites link to or cite your website’s content, it is like a ‘vote’ in favour of that site. All other things being equal, Google and other search engines consider a site with more high-quality links to be of greater authority and places them higher in the search results.

Whilst Google also takes other off-page factors into account, a recent study found a clear relationship between the number of backlinks and Google rankings:

Source: https://backlinko.com/search-engine-ranking

What makes a good link

Google does not treat all links equally. Attributes which signal an excellent quality link include:

Authority of the page

Google’s measure of a site’s authority is called PageRank, after its inventor, Larry Page. Links from authoritative sites (i.e. sites with high PageRank) pass more authority to your site. These are sites which themselves have a lot of incoming links.

Whilst Google no longer publishes a site’s PageRank, other services such as SEM Rush and Moz have built their authority tools:

Relevancy of the site

Unfortunately, obtaining a link from a high authority site is not sufficient. How the linking site’s topic relates to the destination site is vitally important.

For example, if you have a site selling baby products, it is much better to get a link from a parenting blog than a site about cars.

Position on the page

A link’s position on a page is important, with more prominent links imparting more authority. For example, a link hidden in footers and sidebar is not worth as much as links found prominently in a page’s body content.

Naturally placed links

Google gives much more weight to editorially placed links, e.g. where someone has linked to your site as they think is helpful to their readers. Unnatural links are considered a violation of Google’s guidelines.

Links to your site should be natural or placed in similar positions to natural links. For example, you should ask a site owner to add your link to their article if they feel it is relevant. Links that are not given editorially should not be solicited. Example include:

• Blog comments
• Press releases with over-optimised anchor text
• Article directories
• Guest post signatures with over-optimised anchor text
• Advertorials
• Embeddable widgets
• Infographic embeds
• User profile pages
• Guestbooks
• Forum signatures
• Directories that are not moderated

These are low-quality links which will not pass authority onto your site. A site with an unnatural number of low-quality links may reduce search engine performance.

Target keyword in Anchor link text

Google uses the content of the link text to understand the content of the destination page.

In the example above, the link uses the text Paleo Desserts. If many sites link to this site using the same or similar text, then Google might judge this site as an authority on Paleo Desserts.

Be careful, as building many links with exact-match anchor text links is considered spammy. Sites with a natural link profile will have a range of anchor text.

Diverse domains

It is not just essential to get multiple links; those links should be from different domains. Lots of links from the same domain will not have the same effect. A recent search engine ranking correlation study found that the number of linking domains and not the absolute number of backlinks correlated with Google rankings more than any other factor.

Source: https://backlinko.com/hub/seo/backlinks

Dofollow link

An attribute can sometimes be applied to links called “nofollow”. If added, you will not notice any difference if you are a browser. However, if you look at the code of the link, it will look slightly different:

Note the addition of rel=”nofollow” in the code. This tells Google not to pass PageRank to the target page from this link. It will, therefore, not help the target page to rank higher. This differs from standard links, often referred to as “follow” or dofollow links. The no follow attribute is used on sites with lots of user-generated content which have been used in the past for link spam e.g.

• Forum posts
• Blog comments
• Guest book comments
• Editable Wiki pages (e.g. Wikipedia)
• Yahoo! Answer
• Quora
• Guest post signatures

To build page authority, you want to build as many ‘follow’ links as possible.