They also use Yandex for Russian pages, and then there's a hodgepodge of sites that webmasters manually submit/index (i.e. 1990's level of indexing). So DDG is

They also use Yandex for Russian pages, and then there's a hodgepodge of sites that webmasters manually submit/index (i.e. 1990's level of indexing). So DDG is essentially Bing.