Lesson 03 | 08 of 08

Search Engine

A search engine or search service is a program designed to help find information stored on a computer system such as the World Wide Web, inside a corporate or proprietary network or a personal computer. The search engine allows one to ask for content meeting specific criteria (typically those containing a given word or phrase) and retrieves a list of references that match those criteria. Search engines use regularly updated indexes to operate quickly and efficiently. Without further qualification, search engine usually refers to a Web search engine, which searches for information on the public Web. Other kinds of search engine are enterprise search engines, which search on intranets, personal search engines, which search individual personal computers, and mobile search engines. However, while different selection and relevance criteria may apply in different environments, the user will probably perceive little difference between operations in these.

Google search is the world's most popular search engine.Some search engines also mine data available in newsgroups, large databases, or open directories like DMOZ.org. Unlike Web directories, which are maintained by human editors, search engines operate algorithmically. Most Web sites which call themselves search engines are actually front ends to search engines owned by other companies.

Google's main page's unusually spartan design, uncluttered appearance and quick loading time have contributed greatly to the site's mass appeal.Google is a search engine owned by Google, Inc. whose mission statement is to "organize the world's information and make it universally accessible and useful". The largest search engine on the web, Google receives over 200 million queries each day through its various services.

In addition to its tool for searching webpages, Google also provides services for searching images, Usenet newsgroups, news websites, videos, searching by locality, maps, and items for sale online. In 2006, Google has indexed over 25 billion web pages, 1.3 billion images, and over one billion Usenet messages - in total, approximately 12 billion items. It also caches much of the content that it indexes. Google operates other tools and services including Google News, Google Suggest, Froogle, and Google Desktop Search.

Personalized Search
This new improvement to Google search, available on Google Labs, orders your search results based on your search history. And the Search History feature lets you view and manage that history of searches and search results you've clicked on. As you build up your search history, your personalized search results will continue to improve. Note that you must be logged in to your Google Account to use it. Get the search results most relevant to you.Personalized Search orders your search results based on what you've searched for in the past. Early on, you may not notice a huge impact on your search results, but they will continue to improve over time as you use Google.