A link farm is a group of websites that all hyperlink to every other website in the group. Most of the Link farms are created through automated programs and services but some are by hands.
Link farms were originated due to Google’s ranking algorithm and PageRank. PageRank thinks links as votes, where a webpage linking to another page is casting a vote in Page Ranking of that page. Therefore, pages with the most links are valuable. Link farms were created to help in increasing PageRank, but, in recent times, Google and other search engines have updated there algorithms to prevent link farms from appearing at the top of search engine results pages (SERPs).
If you have created a link farms for your website, your website can be penalized by Google and other search engines.
Link farming is considered a “black hat” method of search engine optimization (SEO) because the content on the websites linking to each other is usually not related to each other, because they are not created by a human and is often of a very low quality. Search engines can detect link farms easily and they shouldn’t be seen as a valid long-term search optimization strategy.
Search engines view link farming as a spam. Google and other search engine have implemented procedures to punish those websites that gain inbound links through link farms, rather than organically or through link campaigns with other high-quality sites.
Digital Marketing Service providers who promise to improve your website’s search engine rank may use link farming. In this situation, provider simply posts links in a group of unrelated websites, some of which are designed only for this purpose.
Search engines used to be neglect link farming because they primarily operated on the reasoning that a page has greater authority if a large number of other websites link to it. Now, link farming often fails because search engines have evolved to rank results based on what content will be most useful for the user. This means that a link from a site with trusted content or similar content to the page to which it is linking is worth more than random links from many websites.