The Microsoft Windows Script Host (originally called Windows Scripting Host, but renamed for the second release) is distributed and installed by default on Windows 98 and later versions of Microsoft Windows. It is also installed if Internet Explorer 5 (or a later version) is installed. It provides scripting capabilities far superior to batch files. Beginning with Windows 2000 Server, the Windows Script Host became available for use with user login scripts.
It is language-independent in the sense that it can make use of different Active Scripting language engines. By default it interprets and runs plain-text JScript (.JS and .JSE files) and VBScript (.VBS and .VBE files). Users can install different scripting engines to enable them to script in other languages, for instance Perl. The language independent filename extension WSF can also be used. The advantage of the Windows Script File (.WSF) is that it allows you to use a combination of scripting languages within a single file.
Almost anything that you do with your Windows computer can be automated using a script file. The Windows Script Host is a powerful tool and so, certain viruses make use of its features. Many people and default settings recommend disabling it (or using an antivirus program that blocks scripts) for security reasons.
An easy way to disable the Windows Script Host is to change the default handler for the .vbs, .vbe, .js, .jse, .wsf, .wsh file types to edit rather than run. For a more in depth discussion on securing Windows Script Host, see here.
Windows 98 and Windows 2000 shipped with WSH version 5.1. Windows XP and Windows 2003 shipped with WSH version 5.6. Downloads are available to install WSH on Windows 95 and Windows NT and Windows 98 and Windows 2000 can be upgraded to use the latest version for free by downloading the appropriate files from Microsoft .