A search engine runs delivers results from Bing to you. So why use this instead of Bing -- Ecosia overlays it's own algorithm to improve search results and donates the value of your clicks to reforestation projects. A privacy-friendly tool that does not track or sell data about your searches to others.
The oldest surviving search engine on the web, this search tool was created in 1994 and has database of web resources that it does not share with other search engines. Note: You'll need to scroll down for at least a full page to bypass the advertised websites in the results.