That's a bit of an oversimplification. From the FAQ page:

> When people search, we believe they're really looking for answers, as opposed to just links. For many categories of searches (restaurants, game of thrones, code documentation, etc.), there is usually a specialized search engine (Yelp), content site or other source that does a better job at actually answering the searches than a general search engine does with just links. Our long-term goal is to get you Instant Answers from these best sources.

> To do that, we've developed an open source Instant Answer platform called DuckDuckHack, which allows anyone to propose and develop Instant Answers for DuckDuckGo. On the backend, we have a classification and relevancy engine that selects the best sources for a particular search and displays answers to you in real time, be it for recipes, products, images, and hundreds of other categories.

> In fact, DuckDuckGo gets its results from over four hundred sources. These include hundreds of vertical sources delivering niche Instant Answers, DuckDuckBot (our crawler) and crowd-sourced sites (like Wikipedia, stored in our answer indexes). We also of course have more traditional links in the search results, which we source from Bing, Yahoo, and Yandex.

https://duck.co/help/results/sources

EDIT: changed link to more elaborate FAQ one.