1. INTRODUCTION 1.1. Directories and Search Engines A web directory or link directory is a directory on the World Wide Web. It specializes in linking to other web sites and categorizing those links. It lists web sites by category and subcategory. Usually, they are human compound lists of websites. They don't go looking for web pages; you have to tell them that you found a new web site and you sometimes have to pay in order to add it. Most directories contain only the name of the page and the first paragraph description, so if you want to find a page that contains the key word in the second paragraph you probably won't find that page. This is how search engines appeared. They are like robots that look for web pages taking humans out of the equation. They all have three parts: - a robot (spider) looking for updated web pages, - a database containing a copy of each Web page gathered by the spider, and - a software that enables users to query the index and that returns results in a schematic order. Search engines search the entire page, not only the title and the first paragraph. When you are searching with search engines, you don't search the internet but the copy of the internet of that search engine. Directories are good when you look for specific information, like who created Nokia, or the meteor crater in Arizona. 1.2. Google - the Search Engine Google began in January 1996, as a research project by Larry Page, who was soon joined by Sergey Brin, two Ph.D. students at Stanford University, California. Their search engine was originally nicknamed "BackRub". The name "Google" originated from a misspelling of "googol", which refers to 10100, the number represented by a 1 followed by one hundred zeros. Having found its way increasingly into everyday language, the verb "google", was added to the Merriam Webster Collegiate Dictionary and the Oxford English Dictionary in 2006, meaning "to use the Google search engine to obtain information on the Internet. As it has grown, Google has found itself the focus of several controversies related to its business practices and services. For example, Google Book Search's effort to digitize millions of books and make the full text searchable has led to copyright disputes with the Authors Guild.
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