Links have always been an important part of SEO (search engine optimisation), in fact, they still are, and it looks like they will still be important in the years to come. BUT like everything SEO related, how it was done in the past is much different compared to how it is done today!
There are three classifications of links, these are:
Inbound links - these provide the biggest impact, as they are like a stamp of approval.
Outbound links - only to be used in a way that appears natural to the user, enabling you to associate your site with higher quality sites.
Internal links - help distribute PageRank from inbound links to other pages within the site.
If there is one single piece of advice that goes with all these types of links, it is to link naturally and organically, if it looks bad to humans, most probably it looks bad to search engines too.
Links on pages are like a stamp of approval - the more links a page gets, the more votes they are getting, which can improve their ranking. However, the quantity of links is not all that matters, Google evaluates the quality of the links too. So, ensure that the pages you link to are high quality. Whenever any webpage links to another it’s because the creator considered it some sort of authority on the topic and often the page they are linking to will have information that supports information on the first page. Alternatively, some web designers link to pages for the opposite reason; they may be linking to a page they want to criticise or don’t agree with. Whatever the reason, both of these links are good for the page being linked to. Whether the content is loved or hated, it has provoked a strong reaction, which indicates quality content. If the content of a page sparks engagement then that is a sign of authority, credibility and trustworthiness.
With all of this in mind, don’t be tempted to have too many outbound links - giving links is just as important as getting links. Good quality sites need to maintain their status, so if they are going to link out to other sites, they’d choose a good quality destination, to match their own.
Try to diversify your links, they don't require to be pointed exclusively to your homepage. It is good practice to get backlinks not only from sites with the .com extension, but from other types of websites as well, particularly those that have the .org, .net, .gov, and .edu extensions.
There is plenty of leverage on social media too for link building. Social media platforms are perfect for promoting your content, they reach a wider audience and generate engagement. When using social media for link building, focus on creating and providing content that is appealing to the users of the particular social network, creating a balance between self-promotion and providing content of value. Infographics, image-backed articles and video are all great ways of promoting highly shareable content that generates natural links.
The rules laid out above are not to be set in stone, with anything in relation to SEO it pays to be somewhat flexible, but the main rule that is valid and applies to all rules above is to ensure that all links appear natural.