The three dominant English search engines with their own indexes are Google, Bing, and Yandex (GBY). Many alternatives to GBY exist, but almost none of them have their own results [...] I decided to test and catalog all the different indexing search engines I could find. I prioritized breadth over depth, and encourage readers to try the engines out themselves if they’d like more information.
Seirdy has compiled and continues to update this long list of search engines and their indexes.
Discovered this through Robb Knights' weekenotes.
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