Are you intentionally covering up the fact that there are two versions of Windows 8? Pro and RT have very little in common. Pro indeed can do everything a PC should do, provided you do not need top processing power, and top graphics acceleration, and lots of disk space. External drives solve the disk space problem nicely. I wonder if Microsoft releases docking stations that will allow to add processing and graphics power, or even built in "SETI in Home" features into the OS.
Windows RT can do only the most basic tasks and run a few desktop apps of Microsoft's choosing. Currently I do not see any nontrivial apps in the App Store and I do not see how such apps can be created. Thus, apps wise Windows RT will always lag behind Android and iOS, it is not only younger, it is the hardest platform to go beyond "Hello, World".
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