My first experience with a GUI was the HP-40G calculators. By their nature, they only have arrows and accept/cancel buttons. It featured very advanced symbolic

My first experience with a GUI was the HP-40G calculators. By their nature, they only have arrows and accept/cancel buttons. It featured very advanced symbolic computation features (CAS that would step you through intermediary results), but the magical thing was how equations, rather than being a series of characters, that you piece up into meaningful chunks through parentheses, where actually displayed like mathematicians would write them. Then, to select and edit a specific part of the equation, you have a natural 'box'; numerator/denominator, etc, then you can drill down into the recusirve structure of the mathematical expression. It also means that regular edits are 'correct' by default: delete a parenthesis and your expression is syntactically invalid, whereas "replace the numerator f(x)^2 by 6a" keep you in the space of syntactically valid expressions. In other words, this is the holy trinity of UI: semantic - accessible - efficient The experience is unparalleled to this day, although writing it down I realize more why it was never really reproduced. For a browser, I would imagine having blocks like: A. meta (browser itself) / B. page (DOM) A1. page controls (bookmark, ...) / A2. Navigation experience (font size, dark mode, ...) One can dream :-)