A Windows Script File (WSF) is a file type used by the Microsoft Windows Script Host. It allows mixing scripting languages such as Perl, Object REXX, Python (programming language), Kixtart, JScript, and VBScript within a single file. These types of scripts may also be used to link many other external scripts together using a "src" parameter on the "<script>" tag in a manner similar to HTML. Windows Script Files have the extension ".WSF". A WSF makes reference to each script module in a very basic XML hierarchy as illustrated below.