Directory submission, what is that?

[senthil]

What is meant by directory submission?

[Fli]

Directory submission is when you visit some directory like http://dmoz.org and fill the form to add your website into this directory. You submit the website into the directory which usually means there is a page where is the hyperlink/backlink to your website.

I also think that backlinks from directories may have lower value in Google's eyes. Bulk directory submission i think can even harm.