WPF, Metro, WinRT, UWP

Microsoft made so many changes in so little time.

Here is the little Confusing story behind those frameworks:

• Metro Apps
  For Windows 8, Microsoft had plans to move everything to Tablet and mobile, and started getting rid of PC-focus, for that they invented that thing named Metro Apps. As you may have noticed, Metro apps, appeared once, and then after less than a year, it disappeared.
• WinRT
  As expected Microsoft was wrong and “the PC is still alive” so they had to make an urgent release after the big fat failure of Windows 8, for that they released the Windows 8.1, and they pushed all the ideas they had into that release (majority of the ideas were at beta and not complete) as WinRT.  WinRT was the main framework distributed under Windows 8.1 for the first time, WinRT was intended to replace Metro Apps and mainly to replace the Old Windows API “Win32”.
• UWP
  Universal Windows Platform Apps, was finally released under Windows 10, and you can consider it as a successor of the WinRT, it’s the same technology, but just different Version with a few features... main feature UWP has is that all UWP Apps can run in PC, Tablet, and Phone with almost the same binaries. it’s still fresh technology but it’s worth learning for near future.
• As for WPF
  is the Old framework that was invented to make Rich UI Desktop Applications For PC.
• Windows Forms, aka WinForms
  A Dead Technology, it’s only under maintenance now, no updates will be released anymore for that.
  You might notice that all those Technologies WinRT, UWP and WPF have similar syntax, Objects, Controls…etc, but don’t let that fool you WinRT, UWP are not Based on WPF at all, though they both have .XAML files.