What is a Link Farm?
A link farm is a group of sites that link to one another with the intent of increasing their rankings on search results pages.
The sites in a link farm are often low-quality, with little to no valuable content. Their sole purpose is to manipulate search engine rankings by increasing the number of backlinks pointing to the other sites in the link farm.
Since search engines use backlinks to determine the quality of a site, link farms could trick search engines into thinking a site is more valuable than it is. As a result, the search engine will increase the site’s rankings on search result pages.
Link farms are a form of link scheme. Like all other link schemes, they are considered a black hat SEO tactic and should be avoided, or else Google may deindex your site or hit you with a manual penalty.
That said, link farms should not be confused with link exchanges or reciprocal linking, which are considered a white hat SEO technique and are intended to provide quality backlinks to participating sites.