Hi guys!
New user/IT-noob here.
I was watching this video on window's security
on file hiding ( http://www.metacafe.com/watch/379519/windows_xp_security_hacking_hiding_files_ads/ )
Googling around for info on this area, all I could found is results on its threat, otherwise profound explaination
of its origins. Could anyone explain to me of its origin and purpose in simple? Is this feature necessary in the first place?
Cheers,
John

Hi guys!
New user/IT-noob here.
I was watching this video on window's security
on file hiding ( http://www.metacafe.com/watch/379519/windows_xp_security_hacking_hiding_files_ads/ )
Googling around for info on this area, all I could found is results on its threat, otherwise profound explaination
of its origins. Could anyone explain to me of its origin and purpose in simple? Is this feature necessary in the first place?
Cheers,
John

Alternate Data Streams were made for the NTFS file system so that it could have compatibility with other filesystems, such as Mac OS X's HFS file system, which uses a data fork to store application data. Often, Windows programs store their cache and temporary files in them, too. What makes it so dangerous is that there's no way of disabling it, and the only way to detect it is by using a third-party tool.

For more information on this, I suggest you read this:
http://www.windowsecurity.com/articles/Alternate_Data_Streams.html

Hope this helps