This does not assign a name to a window. What you show will select (put the focus on) the window whose name is currently stored in $$Window--a global variable.
Windows can be named in the New Window script step, the New Window option in Go To Related Records or they can be renamed using Set Window Title. If you don't specify a name when opening a window (leaving that box blank in the dialog or by selecting New Window from the Window menu), FileMaker names the window after your current file name. If there is a window of that name already open, FileMaker appends a number after the file name.