Link building is an important part of SEO, as back-links are a vote of approval from other sites. All links are not equal. A link from a high authority website like RTE.ie carries much more weight than a link from a random site. A link from a site in the same or similar niche will be a lot more relevant than a link from a website which is unrelated to yours. There are many different categories of links, a few which I will discuss here.
An editorial link is a natural link received because of good content and good marketing of the website. The Webmaster does not usually request these but is given by other Webmasters.
An acquired link is one which day Webmaster had to pay for or work for by comments on forums, blogs or other online media.
A reciprocal link is where each of two sites links to each other. Google does not give much credit to reciprocal links.
Forum signature linking is often used as a technique to build links back to the website. Many forum moderators will allow this linking when the user adds value by helping others and answering questions on the forum topics.
Directory links are links for website owners to submit their site under specific categories. Subdirectories are free, and others require payment.
Commenting on a blog post which is relevant to your content can result in a good link back to your website. Most of these blog comment links are no-follow, which are not at all, as valuable as do-follow links.
These are just some of the types of backlinks that are website can have pointed to it. It is also important, how they think is formatted, is it an image, anchor text or naked URL?
A Webmaster has to be careful with the quality and quantity of anchor text links pointing to his site. Branded links such as the brand name of the website, the URL of the site and variations of the URL (http://www.website.ie, http://website.ie, website.ie & www.website.ie) should ideally be the text for the majority of links coming back to the site. Smaller proportions of anchor text with targeted keyword terms will then work better, and the website will steer clear of over optimisation and the Penguin penalty. A lot of websites were this for keyword stuffing of the anchor texts. Keyword stuffing was a method that worked in the past, but now, will damage your site. If your anchor text is over optimised perhaps by some previous SEO work, a press release may help. The press-release will be syndicated to a lot of news sites and will have anchor texts with a naked URL pointing back to your site. This distribution will dilute they anchor text which was over optimised.
To examine the backlink profile of a website, you will need to specific tools, such as AHREFS, Majestic, SemRush or Serped. You can usually get a free trial to these SEO tools, and if you are a single business, this trial period will probably be ideal to try without paying for a subscription. These tools will show you, how many backlinks you have, from how many domains and the anchor text linking. They will also show you the percentage of no-follow versus do-follow links, and the percentage of text links versus image links. These features are all very useful information when you are trying to assess the strength of your current backlinks. You can also use these tools to check out who is linking to similar websites in your niche.
The nature of back-linking has changed. It is not about the number of back-links anymore; it is now about the quality and relevance of the sites and pages that link to your site.