The document describes how internet search engines work. It discusses the main components: (1) crawlers or spiders that crawl websites and index their content; (2) indexing software that extracts information from documents and adds them to a database; (3) search engines allow users to search the database by keywords and return relevant results.

1. How Internet Search Engines Work
* Search engine system
(1,2)
* The indexing software
(3)
* How to use the search engine
(4)
* The Database and The Search Engine
(5,6)

2. Search engine system
Each search engine system called “crawler” or “spider”.
It crawls all home pages are not contained ignore sites and its
links on the Internet and check its contents (graphics files,
sound files, and animation files).
It can take for several seconds to many minutes to crawl each
site it finds, depending on the size and complexity of the site.
The spider sends the information about the contents to
indexing software, as finds documents and URLs.
Crawler and Spider
http://kamezo.cc/blog/entry/44272
http://www.white-cube.jp/cat8/

3. The indexing software
*About indexing software
For example: SKY Index, MACREX, CINDEX™.etc...
*Researchers have been trying for many years to develop
linguistic processing systems.
● Receives the documents and URLs from the agent.
● Extract information from the document(into and put
database)
● Each search engine
○ extracts and index
■ →different type information.
*Quotation by:
● Sentence:
○ http://www.indexers.org.uk/index.php?id=211
● Picture :
○ http://home.windstream.net/wordsmith/
○ http://www.anindexer.com/about/sw/swindex.html

4. How to use the search engine
When you want to know something , you will be use the Internet.
But, do you know how to use the Internet?
If you want to know something , you type words on a web page that describe the
information you want to find.
Depending on the search engine , more than just keywords can be used.
For example, you can search by date and other criteria with some search engines.
The image was quoted from:
http://www.highposition.net/news/what-does-the-recession-mean-for-search-
engine-marketing/

5. The Database and The Search Engine
● The database is searched by the search engine based on the
standard you have set.
● The search engine returns the results in HTML pages.
● The way to return the results is many different.
● You are sent straight to the document that you are interested in.
● The document itself does not exist in the database or on the
search engine site.
http://yutakarlson.blogspot.com/2009/05/funny-restaurant.html

6. References
Wikipedia
http://ja.wikipedia.org/wiki/
Google
http://www.google.co.jp/