A search engine is an information retrieval system designed to help find information stored on a on the World Wide Web.
Search engine indexing collects, parses, and stores data to facilitate fast and accurate information retrieval. Alternatively web indexing is the process of search engines that are designed to find web pages on the Internet.
Index design integrates interdisciplinary concepts from linguistics, Cognitive Psychology, Mathematics, Informatics, and Computer Science. Popular engines focus on the full-text indexing of online, natural language documents. The searchable media types are text, video, audio, and graphics etc. Search engines helps to minimize the time required to find information and the amount of information which must be consulted to other techniques for managing information overload.
Information retrieval (IR) is the science of searching for relevant information, searching for documents themselves, and also searching for metadata that describe data, and for databases of texts, images or sounds from a huge collection of information resources
An IR system is a software that provide access to books, journals and other documents, stores them and manages the document. Searches can be based on full-text or other content-based indexing. Automated information retrieval systems are used to reduce what has been called information overload. A web search engine is a software system that is designed to search for information on the World Wide Web. The search results are generally presented in a lines of results, often referred to as search engine result page (SERPs) commonly called hits. The information may be a mix of webpages, images and other types of files. Search engines also maintain a real time information by running an algorithm on a web crawler.
A Web crawler, sometimes called a spiderbot or simply spider and often shortened to crawler, is an internet bot that systematically browses the World Wide Web, typically for the purpose of Web indexing. Web crawlers copy pages for processing by a search engine which indexes the downloaded pages so users can search more efficiently. Crawlers can validate hyperlinks and HTML code.
Internet content that is not capable of being searched by a web search engine is generally described as the deep web.
One of Computer scientist, Michael K. Bergman coined the term deep web in 2001 as a search indexing term. He defined deep web as invisible web, or hidden web are parts of the World Wide Web whose contents are not indexed by standard web search engines. The content of the deep web is hidden behind HTTP forms and includes many very common uses such as web mail, online banking, and services that users must pay for, and which is protected by a paywall. So deep web content can be located and accessed by a direct URL or IP address, and may require password or other security access.
List of Top 10 Most Popular Search Engines In the World (Updated 2018)
1. Google: The search engine giant holds the first place in search with a stunning difference of 66% from second in place Bing. According to the latest netmarketshare report (January 2018) 74.52% of searches were powered by Google and only 7.98% by Bing. Google is also dominating the mobile/tablet search engine market share with 93%!
2. Bing: Bing is Microsoft’s attempt to challenge Google in the area of search, but despite their efforts they still did not manage to convince users that their search engine can produce better results than Google
3. Yahoo:Since October 2011 Yahoo search is powered by Bing. Yahoo is still the most popular email provider and according to reports holds the fourth place in search.
4. Ask.com:Formerly known as Ask Jeeves, Ask.com receives approximately 0.05% of the search share. ASK is based on a question/answer format where most questions are answered by other users or are in the form of polls. It also has the general search functionality but the results returned lack quality compared to Google or even Bing and Yahoo.
5. AOL.com:According to netmarketshare the old time famous AOL is still in the top 10 search engines with a market share that is close to 0.04%. The AOL network includes many popular web sites like engadget.com, techchrunch.com and the huffingtonpost.com.
6. Baidu: Baidu was founded in 2000 and it is the most popular search engine in China. It’s market share is increasing steadily and according to Wikipedia, Baidu is serving billion of search queries per month. It is currently ranked at position 4, in the Alexa Rankings.
7. Wolframalpha:Wolframalpha is different that all the other search engines. They market it as a Computational Knowledge Engine which can give you facts and data for a number of topics. It can do all sorts of calculations, for example if you enter “mortgage 2000” as input it will calculate your loan amount, interest paid etc. based on a number of assumptions.
8. DuckDuckGo: Has a number of advantages over the other search engines. It has a clean interface, it does not track users, it is not fully loaded with ads and has a number of very nice features (only one page of results, you can search directly other web sites etc). According to duckduckgo traffic stats, as of October 2018, duckduckgo is serving more than 30 million searches per day.
9. Internet Archive:archive.org is the internet archive search engine. You can use it to find out how a web site looked since 1996. It is very useful tool if you want to trace the history of a domain and examine how it has changed over the years.
10. Yandex.ru:According to Alexa, Yandex.ru is among the 30 most popular websites on the Internet with a ranking position of 4 in Russian.
Yandex present themselves as a technology company that builds intelligent products and services powered by machine learning. According to Wikipedia, Yandex operates the largest search engine in Russia with about 65% market share in that country.
Finally, if you search What is the best search engine? in any of the search engines listed above, you will get an answer that Google is the best and most popular search engine and Bing is in the second place (on a Global level).