What is Google?
Who today does not know Google? Google is first and foremost a company (Google Inc.) was founded in 1998 by Larry Page and Sergey Brin, who had set a goal of organizing information globally. Today, Google is known for its search engine, but the company offers a suite of online tools (Calendar, Blogger, Docs, Gmail, Groups, Picasa, Reader, Sites, SketchUp, Talk, English, YouTube, Mobile , Maps, Pack, News, Alerts, directory, Toolbar, Google Chrome, Desktop, Earth, iGoogle, Images, Books) which continues to expand and also its own operating system (Chrome OS).
Google index
To supply the basic indexing Google , robots, called "bots" regularly travel pages on the Internet looking for new links, allowing them to discover new pages will be added to the Google index.
In addition, Google also provides a database archive , called "cache" . When a website is inaccessible for example, or a page has been removed from a Web site, it is always possible to access through the cache function of Google search results .
- The " Google bots " programs are hosted on Google servers , which run Web pages looking for new content, new links. The passage of these "bots" is called "Google dance" .
- The Google index is based on information reported by the " bots " . Google is the search engine with the largest index in the world ( billions of pages: see http://www.worldwidewebsize.com/ ) . For each page indexed , Google combines similar content and calculates poiur each area a PR ( Page Rank ) , a guarded secret formula partly by the publisher. This is the position of PR for positioning the pages in the results of a Google search.
- Cache: For each page covered, Google keeps in its database " cache " 101k of text data (also HTML, DOC , PDF , PPT, ... )
- The Google API is a small external program offered by Google and allows developers to integrate remote query capabilities of search engine. To use it , you must have a free license key ( supplied by Google). Each key can be queried 1,000 searches per day .
Advanced Syntax
Google has a high level language to filter the search results. The following table provides some of the available keywords.
| Directive | Description | Example |
|---|---|---|
| site:domain | Displays a list of all links associated with the domain name | port site:aldeid.com displays a list of all pages contained in the portal aldeid.com and containing the keyword "port" |
| link:page | Displays the list of sites that link to the target site | link:aldeid.com displays the list of sites referring to aldeid.com |
| intitle:terms | Search pages where keywords are specified in the list of terms | To check the qe aldeid.com site does not contain indexed directory listing the contents of its files, we can use the following syntax: intitle: "index of" site:aldeid.com |
| inurl: | ||
| intext: | ||
| related:site | Provides a list of related links (Google algorithm) site provided parameter | related:aldeid.com provides a list of links to similar aldeid.com |
| cache:page | Allows you to search a page in Google's cache | cache:aldeid.com |
| filetype:extension | Allows you to filter the links of research based on an extension | filetype:pdf site:aldeid.com displays the list of PDF documents present on aldeid.com. |
| rphonebook: name and city or country | Allows querying in the telephone directory for residents (U.S.) | rphonebook:william saw NY |
| bphonebook: name and city or country | Can query the directory business (U.S.) | bphonebook:bob robinson LA |
| phonebook: name and city or country | Interviewed both directories previously seen | phonebook:william shakespeare |
| Literal correspondence ("") | Includes all words provided in quotes in the order | site:aldeid.com "taking fingerprint" provides a list of pages that deal with the impression, not the impression or two individual words (socket, footprint). |
| Exclusion operator (-) | ||
| Inclusion operator (+) | ||
| Synonyms (~) | Allows research with oncoming words | Search powerpoint ~ help will research powerpoint AND help or tips, faq, tutorial, etc.. |
| info:domain | Provides information about an area | info:aldeid.com |