Microsoft has added more software in tablet versions that are useful for tablet devices, such as Tablet PC Input Panel, Windows Journal, Sticky Notes, etc. So what's different in tablet specific operating systems? A tablet is a small computer with a touch enabled screen to allow for attracting / writing things on the screen with touch-resistant pen, the operating system needs functionality to handle such a task, this is the reason that Windows XP tablet version is slightly different. The Windows XP Tablet PC version was released publicly on November 2002, it was based on Windows XP Professional, and specifically designed for tablet computers.