A directory is different to a search engine. A directory can be searched in the same way a search engine is searched, but the difference between them is that a directory is human indexed whereas as search engine uses software and computation.
A big distinction between directories and search engines is that directories index web sites and search engines index web pages.
Submitting your commercial site to be reviewed for indexing in Yahoo costs $299 (US dollars). This fee covers the costs of paying a human to review the web site and determine whether or not it will be indexed. After paying the $299, you are not guaranteed a listing. If your site is accepted, then there is a recurring fee of $299 per year.
Submitting your site to DMOZ is a simple process, but again, you are not guaranteed a listing. You submit, wait for a human to review it (this can take up to 3 months, as of 01/2007), and hope that it will be accepted into the listing.
Why submit to a directory?
Two main reasons:
- Targeted traffic
- Link popularity
Directories are an excellent source of targeted traffic. Traffic is one thing… what is the “conversion rate” (customer:visitor ration) on this traffic? There is not much point in generating traffic to your site if the point of having your site is to generate sales. This is the bigger picture of SEO and Internet Marketing.