Why do trees grow downward in computer science?I have a feeling it goes back to a printer, and that a program traversing a tree first prints the root, and uses the notion of a bottomless stack of paper to express the indefinite levels of recursion that might be encountered.References:Trees grow downward, having their roots at the top of the page and their leaves down belowFrom ON HOLY WARS AND A PLEA FOR PEACE.by convention, trees are drawn growing downwardsFrom the Wikipedia article on tree data structures.Real trees grow from their root upwards to the sky, but computer-science trees grow from the root downwardsFrom David Schmidt's lecture notes.
Why do trees grow downward?
computer science;conventions
Just a guess:Tree structures grow downward (root at top, leaves at bottom) because people read from the top of the page toward the bottom. Furthermore, if you were to draw a large tree that spanned several pages, it would be awkward to ask the reader to skip ahead a few pages and then work backward.Furthermore, whether the convention started for the reason explained above or for some other reason, we continue the practice today exactly because it is a convention. We have corresponding terms like top level node (meaning the root) that wouldn't make as much sense if we drew the structure with the root at the bottom.