Link popularity represents the total amount of links that point to a certain website. This term represents a measure of the quality and number of links pointing to a site.

Link popularity is taken into consideration as a consequence of search engines algorithms that have to emulate human intelligence. Just think about the purpose of Google and all the other major search engines. Search engines only want to offer their users the best searching services ever. That's why they need really relevant results for each query.

Considering the web has developed a lot, search engines can not rely just on the on page content and optimization. That's why the off page factor is essential. The off page factor is pretty much similar to human social relationships.

The more inbound links a site has, the better it will be seen by search engines. In order to have a better understanding of this phenomenon, I'll try an analogy with the human world.

A site linking to yours is giving you a sort of vote that will count for search engines' opinion. It's just like one person is receiving a recommendation from another, so that a third person has a better opinion on him.

As search engines are trying to find relevancy, inbound links are essential for any site that's trying to succeed online. If do a simple search on Yahoo, you can see how sites ranking on the first pages of search engines have thousands of links pointing to them. Most of them have links from general directories, niche directories, local directories, and articles on different sites, press releases, and blogs submitted to specific directories, related and non-related sites.

One way links from directory submission and article submission is a must do for every site struggling to get to page 1. Directory submission can not be done multiple times, as directories don't allow duplicates of an URL. It's a link building process that can be done only once. That's why you should not skip this link building must do.