Windows XP was released for sale in 2001 and was probably Microsoft's most popular, critically acclaimed operating system. It was simple to use and got everything right. Microsoft continued to sell XP until about 2010 even though it was replaced by Windows Vista, then Windows 7, and then Windows 8, and their various interim improvements. The company sold more than 400 million copies of XP in its first five years.
But in April, $4. That doesn't seem to have shifted user-behavior, however. As $4 shows, people haven't really shifted away from XP. $4
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