Link Farm According to Wikipedia
“On the World Wide Web, a link farm is any group of web sites that all hyperlink to every other site in the group. Although some link farms can be created by hand, most are created through automated programs and services. A link farm is a form of spamming the index of a search engine”
So this is what is well known to many, but if you still don’t get it, try it this way:
On a page there are thousands of links, linking to different websites or blogs. Trying to make it look like backlinks to search engines and gain more credibility that way, then that page or domain is known as link farm.
What happens to link farms and to the sites that link to it?
This method may have been a success in 2000’s but now it is of no use, other than that of usefulness, it is way too harmful for you to link to a link farm as it search engines don’t only consider it a spam, but also an illegal way of trying to surpass the Google algorithms.
Other consequences of linking to a farm site
Other than considering your link as a spam it may also result your domain to permanent ban from search engine results page.
And if not that it may actually keep you in the sandbox.
My take on this:
If you are actually looking for ways to increase backlinks then do it the correct ways, don’t use illegal ways to do so.