<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> Windows XP (codenamed Whistler) is a personal computer operating system that was produced by Microsoft as part of the Windows NT family of operating systems . It was released to manufacturing on August 24, 2001, and broadly released for retail sale on October 25, 2001 . </P> <P> Development of Windows XP began in the late 1990s as "Neptune", an operating system built on the Windows NT kernel which was intended specifically for mainstream consumer use . An updated version of Windows 2000 was also originally planned for the business market; however, in January 2000, both projects were shelved in favor of a single OS codenamed "Whistler", which would serve as a single OS platform for both consumer and business markets . Windows XP was a major advance from the MS - DOS based versions of Windows in security, stability and efficiency due to its use of Windows NT underpinnings . It introduced a significantly redesigned graphical user interface and was the first version of Windows to use product activation in an effort to reduce its copyright infringement . </P>

Windows xp is which type of operating system
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