You can reduce a lot of specialized knowledge to "trivia" by noting how it can be easily looked up, nowadays. But asking candidates about data structures is ha

You can reduce a lot of specialized knowledge to "trivia" by noting how it can be easily looked up, nowadays. But asking candidates about data structures is hardly the same thing as asking them to spew out memorized responses. There's a big difference between "tell me the exact steps involved in the rebalancing algorithm for an AVL tree" and "here are some requirements for an application, what data structures would you consider using and why?" These sort of questions are designed to test for generalized background knowledge and experience working with data structures, not simply whether the candidate knows exactly what a skip list is. It also demonstrates a general ability to apply CS knowledge to real-world situations.