I had a 3-year old installation of Homebrew in /usr/local/Library/Homebrew. It didn't update properly, so I reinstalled it (without, unfortunately, uninstalling first). This time, Homebrew installed in /usr/local/Homebrew.
Not only are the folder locations different, but the subfolders also are different. Is the old installation deprecated and can I delete it? Or does the new installation depend on the old installation? This is under Mac OS Sierra.