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 radically different ways.
Crawler-Based Search Engines
Crawler-based search engines, such as Google, create their listings automatically. They "crawl" or "spider" the web, then people search through what they have found.
If you change your web pages, crawler-based search engines eventually find these changes, and that can affect how you are listed. Page titles, body copy and other elements all play a role.
Human-Powered 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, or editors write one for sites they review. 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 site, with good content, might be more likely to get reviewed for free than a poor site.
"Hybrid Search Engines" Or Mixed Results
In the web's early days, it used to be that a search engine either presented crawler-based results or human-powered listings. Today, it extremely common for both types of results to be presented. Usually, a hybrid search engine will favor one type of listings over another. For example, MSN Search is more likely to present human-powered listings from LookSmart. However, it does also present crawler-based results (as provided by Inktomi), especially for more obscure queries.
Examples of search engines on the internet.
1. Google
Google was founded by Larry Page and Sergey Brin in the year 1996.Google today has sky as its limit and all of us know that even an illiterate person know what google is.Google’s headquarters are located at 1600 Amphitheatre Parkway, Mountain View, California,USA.Today,Google is not only a search engine it is far more than that today google has now came up as a company and it serves the whole world.
2. Yahoo
Yahoo was founded by Jerry Yang and David Filo in the year 1994 but till 1995 Yahoo was called Jerry’s Guide to the World Wide Web but later in 1995 it was renamed as yahoo!.Yahoo today gives equal competition to Google and other big Internet boons.Yahoo’s headquarter are located at 701 First Ave. Sunnyvale, California, United States.
3. Baidu
Baidu is a Chinese company which serves China and Japan only but due to its high traffic it is ranked 6
th on Alexa. Baidu offers search in Chinese only. Baidu’s headquarter are located at Beijing, China. Baidu was founded by Robin Li and Eric Xu.
4. MSN
Though Msn now has been converted into bing but it was a great search engine before that. MSN is a product of Microsoft and MSN is ranked 11 on Alexa.MSN serves the whole world. MSN is a portal website which makes MSN a good competitor of other search engines. MSN was launched by Microsoft on August 24, 1995.
5. Bing
Bing has a really nice full form which is “Bing is not Google”.Although this is not the official full form of Bing, Bing itself is a word. Bing is a product of Microsoft, Microsoft converted msn into bing. Bing’s rank on Alexa is 24 which is really nice.Bing has spent only a year in the search engine market but it has prospered a lot.Bing was launched on June 3, 2009.
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