DuckDuckGo does not store any personal information, e.g. IP addresses or user agents: see our privacy policy for details. We also have an encrypted (SSL) version, two non-JS versions (HTML & lite), aTor hidden service (about), several privacy settings (including POST & RefControl), and we allow you to use URL parameters instead of cookies to store settings.
We've tried to explain the consequences of tracking as it applies to search results in our donttrack.us and dontbubble.us infographics.