Really? For that exact query, I get the Wikipedia page for "Salt (Cryptography)", "How to Hash Passwords", and "Salt the Hash - Security tutorial"... you get the idea[0].
AFAIK, the stuff you're seeing at the top is their 'zero click' information, which Google never provided (until after DDG added it and promoted it as a selling point). That's a little hit-or-miss, sure, but the actual search results of DDG are generally just as relevant.
I've been using DDG as my primary search engine for years now - I still resort to "!g" searches sometimes, but I have to do it far less than I used to.