About Search Engines

The term "Search Engine" is often used generically to describe both crawler-based Search Engines and human-powered directories. These two types of Search Engines gather their listings in a very different way.

Search Engines
Crawler-based Search Engines, such as Google, Yahoo and MSN create their listings automatically. They "crawl" the web, then people search through what they have found. If you change or add your web pages, crawler-based Search Engines eventually find these changes, and that can affect how you are listed. Page titles, content, inbound links and other elements all play a key role.

Directories
A human-powered directory, such as the Open Directory, depends on humans for its listings. You submit a short description to the directory for your entire site. A search looks for matches only in the descriptions submitted.

Changing your web pages has no effect on your listing. Things that are useful for improving a listing with a search engine have nothing to do with improving a listing in a directory. The only exception is that a good website, with good content, might be more likely to get reviewed for free than a bad website.

"Hybrid Search Engines" Or Mixed Results
In the early days, it used to be that a Search Engine either presented crawler-based results or human-powered listings. Today, it's common for both types of results to be presented. Usually, a hybrid Search Engine will favour one type of listings over another.

>>Search Engine Decoder ­ Relationship Chart
This chart shows the relationships between the various search engines and directories.