Backlinks are links from one site to another.

Backlinks occur when one site links to another site. Most links will lead users to a homepage of another site, however it is usually better in terms of a site's DA if this backlink directs users to the most relevant landing page. For instance, if a cosmetic ecommerce site sent one of their products such as an anti-wrinkle cream to a blogger, then it is ideal that this blogger links to the category page of that product (i.e. skincare category page), as this will allow users to browse the other available products plus possibly resulting in more potential purchases. Backlinking is one of the best ways to increase the Domain Authority of your website.