Tiered link building organizes backlinks into two groups. Tier 1 links point...

https://www.unitedbookmarkings.win/tiered-link-building-uses-two-levels-of-links-to-boost-your-site-s-authority

Tiered link building organizes backlinks into two groups. Tier 1 links point directly to your site and carry the most value. Tier 2 links support those Tier 1 links, boosting their strength and helping improve your rankings