Open the Current Working Folder from the Command-line/Terminal in Windows, Ubuntu or OS X

Sometimes you need to use the operating system file manager rather than a terminal so a quick way of opening it can be seen below. For the Windows command line:

explorer .

The OS X terminal:

open .

The Ubuntu console:

nautilus .

This will work for parent folders ".." as well as current directory. Note, in case you are interested to do the same in Haiku OS just use the OS X version.