There isn't much to it. Windows, for example, implements plumbing as the ability for the user to double-click, in an Explorer window, on, say, a PDF file and ha

There isn't much to it. Windows, for example, implements plumbing as the ability for the user to double-click, in an Explorer window, on, say, a PDF file and have it opened automatically using the default PDF viewer; the command-line equivalent is the 'start' command.