Directory submissions used to be a valid, white hat SEO strategy. The goal of a directory was to offer a site on which content could be placed and then linked back to another website. Essentially, it was at that time a good way to get lots of inbound links which made it perfect for SEO purposes. However, with the recent updates to the Google algorithm, specifically the Penguin update, a once popular and legitimate practice has become black hat.
There are many different types of strategies that are used in an effective SEO campaign. These might include things like content creation, on page and off page optimization, Metatag data, social chatter and also backlinks. It’s common knowledge that search engines like Google are always making changes to the algorithms that they use to rank sites. Of late, there has been a lot of talk about backlinks. Gathering backlinks used to be a great white hat SEO tool and the more a site could obtain, the better its ranking. But people farmed and purchased backlinks just for the sake of getting backlinks. In many (maybe most) cases, the backlinks had no relevancy with the content or the site they were linked to. Google updates have been made in an attempt to clean it up. Gathering backlinks for the sake of having a large number of other sites linked to a site is now considered a black hat practice. Humans frown on it, and Google will penalize a site that is guilty of it. But this does not mean that backlinks have no value whatsoever, especially when it comes to SEO. It’s just important to know which ones really count and why.