DuckDuckGo is a search engine meta-engineer located in Valley Forge, Pennsylvania. It stands out by using crowdsourcing information from other sites (like Wikipedia) in order to enrich the traditional results and improve relevance. It also offers its own search engine.
The philosophy of this search engine is to preserve privacy and not to store any personal information about users [2], [3] (IP addresses and numeric traces like the signature of the browser). However, by default, DuckDuckGo relays sponsored links (advertisements) on its search engine.
DuckDuckGo has been in strong growth since PRISM / XKeyscore [4]; Its traffic ranks 1152th globally on 29 August 2013 [5], according to the research firm Alexa [6]. In June 2015, it becomes 508th [7].
It devotes part of its revenues to finance free projects [8], [9].