Updated June 16th, 2019.
It’s easy as 1, 2, 3! Actually, it’s easy as 1, 2, 3, 4. And what is it that’s so easy? Switching between the Finder’s four views, that’s what. Open a Finder window and try: all it takes is ⌘-1, ⌘-2, ⌘-3, and ⌘-4.
Below: one window, four ways. (Click a thumbnail to start the slide show.) The View you choose is a window-by-window setting, so if you want to see icons in one window, and a list view in another, go right ahead. Just do it from the keyboard instead of using the mouse. It’s a lot faster.