Yesterday we discussed the crawler based searchengines like google.com.
Today we shall go deeper into directories.

Here are the four major searchengines types again:

1) crawler based search engines.
2) directories (edited and maintained by humans)
3) hybrid engines (META engines and engines using other engines’ results)
4) paid inclusion engines and pay-per-performance

Directories (edited and maintained by humans)

Directories are often mistaken for searchengines, but they are entirely different.

One of the differences is that crawler based searchengines keep visiting your website after it has been indexed and detect the changes you made to your website. The same does not apply to directories who do not keep track of changes on your website after it has been submitted.

At a directory you have to manually submit your website and experienced editors will then decide if you are allowed in their directory. The editors will check your website according to certain (rigid) guidelines and check the content, design, functionality, Google Pagerank™ and such instead of using automated crawlers like crawler based searchengines do.

This method of working will insure quality websites added to a directory.

It is important, if you want to be added to such a directory, to submit a relevant and precise description to the directory editor, as well as to take the whole manual submission seriously.
In SEO(search engine optimization) you should treat manual directory submission as seriously and responsible as possible.

For sure, ranking of a website in a directory works completely different than a crawler based search engine. An example of such a directory is dmoz.org (ODP (Open Directory Project)).

If your website is listed in such a directory it will be quite influential to your positions in crawler based search engines.
This means when your website is added to the dmoz.org directory it will influence your rankings positively on the crawler based searchengines that also use the directories to enrich their databases.

You could say that being added to the dmoz.org directory is an honor. It will also provide you with a pagerank 8 backlink and your website will be boosted and indexed within 1-7 days instead of a few months.

Top directories include Yahoo!, ODP (Open Directory Project) and Ask Jeeves.

Tomorrow:
Part 3 - Hybrid Searchengines