Pathname represents the name of a file or directory on the filesystem, but not the file itself. The pathname depends on the Operating System: Unix, Windows, etc. This library works with pathnames of local OS, however non-Unix pathnames are supported experimentally. A Pathname can be relative or absolute. It's not until you try to reference the file that it even matters whether the file exists or not. Pathname is immutable. It has no method for destructive update. The goal of this class is to manipulate file path information in a neater way than standard Ruby provides. The examples below demonstrate the difference. All functionality from File, FileTest, and some from Dir and FileUtils is included, in an unsurprising way. It is essentially a facade for all of these, and more. WWW: https://github.com/ruby/pathname