Pandas helped save PageRank
Google has revolutionized the way that we use the internet. Its name has joined the tanks of Advil, band aid and kleenex as becoming synonymous with the industry they inhabit, to the point where i never hear the term search engine anymore, rather just “google it”. A key part of googles dominance was the PageRank algorithm which relied on a simple premise, pages that had other sites link to it more frequently was probably more important and more useful to searchers than one that was never linked to. This idea developed by Larry Page and Sergey Brin at Stanford was key in googles rise to success. However it became problematic in the early 2010’s. Loopholes in the system were being exploited and sites of little use to users were reaching prime positions on search results.
To combat this problem Google released several updates to their system and made the system secret. The first and most important of these was Panda. Panda worked to fight against several problems. The first was the penalty levied in the system against short pages, to combat “content farms” of small pages that linked back to pages and were solely intended to boost rankings of another site. The second was that it struck back at “thin” websites full of keywords over useful content. These strategies combined to staunch the bleeding and helped prevent PageRank from being a problem and started it back on the road to being a key element of Googles success.
https://www.sitepoint.com/google-algorithms-explained-part-1-dont-be-spam/