Lists are tuples are very common features for languages. Arrays and lists have been around for some time, so they are almost expected. Python does away with arrays, understandably so, and it almost makes little sense to keep they around for Copper. Tuples, on the other hand, seem primarily for mental models, but can be useful in preventing misuse and accidental deletions or additions of elements as well as providing convenient means for extraction. They sort of fill the gaps for simplicity that lists, arrays, and general objects don’t fill. Both of these should be discussed in detail.