While on your desktop (either with no windows open or with the desktop focused) type / (forward slash). Now type in a folder path and hit Enter. The directory will be opened in a new Nautilus window. On top of that, it will also autocomplete most paths.
For a quick usage example, say I want to get to /var/lib quickly. Instead of having to open Nautilus and navigate to it, I just type the path out on the desktop. /var/lib Enter, and boom, I’m in the folder.