I've used Sort method several types both in Java and JavaScript but they way it's used it as a library function, I don't need to write my own sorting algorithm. Same for Data Structure commons ones I've used are found in Java Collections - ArrayList, LinkedList, HashMap, Set etc. For Deep Learning have used several algorithms that are best practices and common data structures like Tensors and Vectors. I realize the value of knowing the theoretical underpinning but practically speaking these are only ever written one by library creators, no idea why companies insist everyone to know these and implement by heart, they can ask much more interesting practical problems.