Earned editorial backlinks
These are the hardest to get and the most valuable. Links are created by real journalists, bloggers, industry publications. Types of content they link to are case studies, in-depth Q/A, data, tools, and information that they want to link to naturally.
What “earned” means here: the link comes from a paragraph inside another websites content, but on a domain Google trusts. Not a spammy footer link or sponsored link dressed up as an article.