What Are Backlinks in SEO? Everything You Need to Know

Inbound links, also known as backlinks or incoming links, are essentially hyperlinks that connect one website's page to a page on a different website. Search engines, such as Google, interpret backlinks as endorsements, which play a significant role in page rankings.

There are two primary reasons why backlinks are a cornerstone of SEO (Search Engine Optimization):

You can employ two strategies to analyze a website’s backlinks.
The initial approach is applicable only to websites you manage. The alternative method allows you to examine backlinks to any website or webpage.

Google Search Console, a no-cost resource, is a great starting point for reviewing your site's backlinks.
After logging in, navigate to the “Links” section in the sidebar. The “External links” count denotes the total amount of unique backlinks to your site.

Be aware that Google Search Console is limited to displaying the top 1,000 links in the app and omits some insightful SEO metrics that could be crucial for a detailed backlink analysis. For an expanded dataset at no cost, consider utilizing Ahrefs Webmaster Tools.
After creating a project in Ahrefs, click on the Backlinks tab on your dashboard.

You'll be directed to a detailed backlinks report within the Site Explorer tool, showcasing all the backlinks to your site along with pertinent information.

Begin with a service like Ahrefs’ complimentary backlink checker for this purpose.
Simply input a domain or URL and select “Check backlinks."

The tool will present the total count of backlinks and referring domains (unique website links), as well as the top 100 backlinks.

The effectiveness of backlinks varies greatly. Consider these characteristics that influence the quality and effectiveness of a backlink. They are useful for evaluating your existing backlinks and when seeking out new, high-value backlink opportunities:

A backlink originating from a robust webpage typically carries more "authority" than one from a weaker page.

Our research into page-level authority has repeatedly revealed a strong link to organic search traffic.
However, it's not a given that all backlinks from authoritative sites will pass on more authority. The authority passed is diluted among all outbound links on the page due to the principles of the PageRank algorithm.

To assess the authority of a backlink, you might use Ahrefs' UR metric in the Backlinks report within Site Explorer. (This metric is also available in other relevant Ahrefs tools.) A higher UR indicates a more authoritative backlink.

Backlinks that come from websites within the same niche or industry as yours are generally more beneficial. Google's "How Search Works" guide supports this notion:

For instance, a plumber will find more value in a backlink from a site about boiler installation than one from a site about feline care. The more relevant the linking page's topic, the more valuable the backlink.

The visible, clickable text in a hyperlink is known as the anchor text.

According to Google's original patent, anchor text affects search engine rankings.

The anchor text for any backlink can be identified through a backlink analysis tool such as Ahrefs' Site Explorer.

A nofollow backlink carries an attribute that signals to Google the suggestion to disregard the link for authority passing purposes, as updated in 2019.

Conversely, a followed link lacks the nofollow, sponsored, or UGC attributes, allowing it to potentially pass on authority.

Although nofollow links traditionally do not impact rankings significantly, it's wise to focus on acquiring followed links. However, as nofollow has transitioned to more of a suggestion, a nofollow link from a pertinent, authoritative page can still be valuable.

Such backlinks can be pinpointed using the filtering options in the Backlinks report of Site Explorer.

The likelihood of a link passing more authority increases if it's prominently placed, as users are more likely to click on it.

Bill Slawski discusses this in relation to Google’s revised "reasonable surfer" patent:
A link that is central to the main content, is styled distinctively, and holds engaging anchor text may transfer substantial PageRank. Conversely, a link that's less visible, like one in the footer, matching the general text style, or with unengaging anchor text, might not convey as much PageRank.

This insight should guide your link acquisition efforts. If your link is one among many, such as in a sidebar or footer, it might be prudent to look elsewhere.

Tools like the "Backlink type" filter in Site Explorer can assist in identifying backlinks embedded within content.

Since Google ranks pages rather than whole websites, aim to build links to the specific page you wish to rank.

However, it can be challenging to gain links to certain types of pages, such as commercial ones, because informative content generally attracts more links. In such cases, use internal links to channel authority from well-linked pages to those that are less attractive but important.

Some platforms allow manual link submission. While easy, these links may be of low value or even be seen as spam.
A reliable method is to list your site in relevant local directories, beneficial for local search and discovery.

This involves requesting links from others, but success depends on a strong value proposition. Some effective strategies include:

Purchasing backlinks is highly discouraged and poses a risk of penalization by Google. This is different from employing reputable link-building services that adhere to white-hat practices.

Backlinks are naturally earned when your content is discovered and valued enough to be linked to. High-quality, promotable content increases the likelihood of earning these links.

Specifically, avoid:

Steer clear from schemes that appear spammy, low-quality, or part of a link exchange, as these can lead to negative ranking impacts or penalties.

While backlinks are integral to ranking, especially in competitive searches, the value of a link often correlates with the effort required to obtain it. Avoid shortcuts and focus on fostering genuine, quality link-building practices.