What you've just seen is Visual Basic being executed by your web browser.
Didn't see anything ? Good. That probably means that your browser did not execute the Visual Basic scripts on this page, which protects you against harmless jokes and not so harmless tricks people can play with VBS on web pages.
VBS is a rather powerfull scripting language. It is capable of reading files, get acces to your computer configuration, and modify them, or delete them, and so on. It can be used by system administrators to create or modify user accounts and security settings etc. All that can also be done by a script embedded in a web page, so that the 'web page' becomes system administrator of the PC that visits that site. Scary, isn't it ?
Look here to see some Visual Basic scripts. See also this example of - malicious - website with vbs.
And what if those scripts could be used to create viruses ? Look here to see how easily a Visual Basic script can become a virus.