How to get windows username and print it into HTML Doc. using ASP ?

How to get windows username and print it into HTML Doc. using ASP ? HI ..
I have a network that's content AD and Small Intranet page
I want to display welcome message when the user open this page
the message will be "Welcome %unsername%"
username = the logged in (to windows) username
But how to get and print the username into HTML Using ASP?
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