I had this in mind, isnt it what it is, hiding behind a popular name 'directory'. Definition of a link farm: A site where everyone submits their links. Definition of a directory: A site that has categories to which people submit links. I see a pattern, what do you think?
Directories generally don't contain a lot of spamming links and so forth. Take a look at the stuff "posted" to a true FFA link farm... you'll see a big difference I'm sure.
So basically, the difference between both is 'is it spammed with uncategorized links or not'. I guess a directory is much more moderate in links then farms. I use directories all the time, it's just that I'm afraid of the search engines when I do that... They might think i'm spamming my backlinks and that would lower my PR, no?
I've seen it explained many times that a link to you cannot be negative, it could just be zero. The problem is, if it was negative, a competitor could spam you to all the link farms and reduce your PR, and that can't be something a real search engine allows to happen. What is likely is that link farms cheapen the links so that they are next to worthless... as it can be done automatically and algorithmically. However, it is also possible they analyze the site to determine whether or not it looks like spam heaven also. Hard to say.
directories are not link farms. i read some where that a link from good directory has more weight than a link from content site
I think that would be the answer to your question. Difference is, linking to spammy sites(bad neighbours) and quality sites.
In FFA pages usually links are automatically added where as directory listing are reviewed by humans so cannot be considered as spam by search engines
1) directory are categorized, so only related page will show on same page 2) directory are human edited, so site that is too spammy won't get in. however, if they editor accept every single submission, it will become a FFA link farm. BTW, site like linkdump is also FFA link farm IMHO
Don't the descriptions of the sites change things from a straight link farm? They add content on a particular topic - the directory category. Isn't that what drives the PR of the directory and value of the backlinks?
Directories are human edited and categorized. There are a lot of popular directories like yahoo directory, demoz. There is no popular link farms which produce significat traffic.
Actually, a directory and a link farm are totally different things. A link farm is a network of sites or pages interlinked together. A directory is just a colllection of links to other sites.