Overview
DuckDuckGo's results are a compilation of "about 50" sources,[39] including Yahoo! Search BOSS; Wikipedia; Wolfram Alpha; Bing; its own Web crawler, the DuckDuckBot; and others.[1][39][40] It also uses data from crowdsourced sites, including Wikipedia, to populate "Zero-click Info" boxes – grey boxes above the results that display topic summaries and related topics.[41]
DuckDuckGo positions itself as a search engine that puts privacy first and as such it does not store IP addresses, does not log user information and uses cookies only when needed. Weinberg states "By default, DuckDuckGo does not collect or share personal information. That is our privacy policy in a nutshell." However, they do maintain logs of all search terms used.[42]
Weinberg has refined the quality of his search engine results by deleting search results for companies he believes are content mills, like Demand Media's eHow, which publishes 4000 articles per day produced by paid freelance writers, which Weinberg says is, "...low-quality content designed specifically to rank highly in Google's search index." DuckDuckGo also filters pages with substantial advertising.[43]