Major search engines generally provide listings from a variety of sources, which they may get from third-party search providers or through their own efforts. The table below shows where each search engine gets the main results it displays. See beneath the chart for a full explanation of each column.
Clicking on a search engine's name in the first column of the chart provides a description of that search engine and a link to it, from Search Engine Watch's Major Search Engines page.
Interested in being listed in the results at one of the search engines shown below? Just click on the other links in the chart. They bring up submission help from Search Engine Watch's Search Engine Submission Tips section.
|Search Engine||Type Of
|AllTheWeb.com (FAST)||Crawler||AllTheWeb.com (FAST)||Overture
(& late 2002, also Lycos)
|AOL Search||Crawler||Open Directory|
|Ask Jeeves||Crawler||Teoma||Open Directory|
(& late 2002, also Lycos)
& backup from Inktomi
|LookSmart||Human||LookSmart||LookSmart||Backup from Inktomi|
(& late 2002, also Lycos)
|MSN Search||Human||LookSmart||Overture||Backup from Inktomi|
|Netscape Search||Crawler||Open Directory|
|Overture||Paid||Overture||Overture||Backup from Inktomi|
|Open Directory||Human||Open Directory||n/a||n/a|
|Yahoo||Human||Yahoo||Overture||Backup from Google|
While search engines display results from many different sources, usually the results from one particular source will be most dominant. These are considered to be the "main" results for that search engine. For example, in a search at Google, the main results are typically editorial listings that come from Google having crawled the web.
Here is more information about the "type" of main results that are listed on the chart:
- Crawler: the main results are compiled by having crawled the web.
- Human: the main results come from listings compiled by human editors.
- Paid: the main results come from paid listings.
- Clickthrough: main results come from measuring what people click on. See the Using Direct Hit Popularity Results page for more about this.
Provider Of Main Results
Some search engines gather their own listings for the main results they display. For example, Google crawls the web itself for the main results it shows, while Yahoo uses its own human editors to compile listings. Other search engines use third-party search providers for their results. For instance, the main search results at AOL come from Google's crawler-based listings. This column shows who provides the listings for main results, be it internal work or a third party.
The Who Powers Whom? search engine alliances page shows third-party partnerships in a different way. On that page, you can more easily see who the significant search providers are and the search engines they power.
For help in getting listed with a particular search provider, read the Essentials Of Search Engine Submission guide, for a step-by-step process to the basics of submitting to key players. Or, click on any of the chart links for submission help about a specific search provider. Also consider becoming a Search Engine Watch member, to gain access to detailed information about how these search engines work.
Every major search engine has paid listings that are also presented alongside its editorial results. This column shows who provides those paid listings. For example, Overture provides paid listings to many different partners.
Also see the Buying Your Way In page for detailed information about paid listing partnerships.
Directory, Backup & Other Results
Most search engines where the main results come from crawling the web will also provide human-powered "directory" results in some way. For example, in a search at Google, "category" links that lead to human-compiled information often appear at the very top of the search results page. This column shows where directory information comes from, from the crawlers that provide this human directory information in some way.
For search engines where the main results come from human work, it's common for them to have a "backup" or "fallthrough" partnership with a crawler-based search engine. For example, if a search at Yahoo fails to find a match in Yahoo's own human-compiled information, then matches from Google provide answers. This provides backup against having no matches at all. This column shows where the backup results come from, for search engines where this is in operation. For Overture, it shows what happens on the Overture site itself, when there are no paid results.
Other Relationship Charts
Several other sites chart the relationships between search engines. Below are some links you may wish to try:
Bruce Clay's Search Engine Relationship Chart
Long-standing graphical look at relationships between different search engines. This is in PDF format, so be sure to have a viewer before clicking on the link. Selecting any search engine "node" takes you to a web page within Bruce Clay's site with more information about that search engine.
Brett Tabke's Search Engine Relationship Chart
Compiled by WebmasterWorld.com's Brett Tabke, this table provides a comprehensive review of who powers whom for major US-based search engines and some European sites.
European Search Engine Chart
Lists how various European search engines get their results.
Integrated Resource Management's Search Engine Tips Chart
Details about various major search engines, such as who powers whom, submission links and other information, all in table format.
PA WebSearch Top 15 Search Engines & Directories Charts
Offers three graphical charts in PDF format showing editorial relationships, indexing fees and paid listings partnerships.
Australian Search Engine Relationship Chart
From Australian-based search engine marketing firm Sinewave Interactive, this is a graphical illustration of relationships between major Australian search engines.