Google Search (or Google Web Search) is a web search engine owned by Google Inc. Google Search is the most-used search engine on the World Wide Web, handling more than three billion searches each day.
Facebook is an online social networking service. Its name comes from a colloquialism for the directory given to students at some American universities.
YouTube is a video-sharing website, created by three former PayPal employees in February 2005 and owned by Google since late 2006, on which users can upload, view and share videos.
Twitter is an online social networking and microblogging service that enables users to send and read "tweets", which are text messages limited to 140 characters. Registered users can read and post tweets, but unregistered users can only read them.
Yahoo! Inc. is an American multinational Internet corporation headquartered in Sunnyvale, California. It is globally known for its Web portal, search engine Yahoo Search, and related services, including Yahoo Directory, Yahoo Mail, Yahoo News, Yahoo Finance, Yahoo Groups, Yahoo Answers, advertising, online mapping, video sharing, fantasy sports and its social media website
Bing is a search engine that brings together the best of search and people in your social networks to help you spend less time searching and more time doing.