The exact effects are a Microsoft trade secret, but you can read this to see if that answers your question -> http://members.aol.com/axcel216/secrets.htm#FORMAT
The /S would be used for Windows 1,2,3, 95, 98 and if you wanted to boot DOS.
There is an usage for such a format in odd and not well documented alternate methods of installing Windows ME, NT, 2000, XP and 2003, but this is best left to those who have the time to spend on this.
Bob
When i format my hard drive should i use format c: /s or format c: /u ive heard different from several people. And what does s and u stand for?

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