Initial WPF content migrated (#17)

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dotnet-desktop-guide/framework/wpf/advanced/base-elements.md

@@ -0,0 +1,37 @@
+---
+title: "Base Elements"
+ms.date: "03/30/2017"
+f1_keywords: 
+  - "AutoGeneratedOrientationPage"
+helpviewer_keywords: 
+  - "base elements [WPF]"
+ms.assetid: 55034aa5-3c1d-442a-8293-f4692d8ea6ae
+---
+# Base Elements
+Four key classes--<xref:System.Windows.UIElement>, <xref:System.Windows.ContentElement>, <xref:System.Windows.FrameworkElement>, and <xref:System.Windows.FrameworkContentElement>--implement a substantial percentage of the common element functionality available in WPF programming. These four classes are referred to in this SDK as the base element classes.  
+  
+## In This Section  
+ [Base Elements Overview](base-elements-overview.md)  
+ [Freezable Objects Overview](freezable-objects-overview.md)  
+ [Alignment, Margins, and Padding Overview](alignment-margins-and-padding-overview.md)  
+ [How-to Topics](base-elements-how-to-topics.md)  
+  
+## Reference  
+ <xref:System.Windows.UIElement>  
+  
+ <xref:System.Windows.ContentElement>  
+  
+ <xref:System.Windows.FrameworkElement>  
+  
+ <xref:System.Windows.FrameworkContentElement>  
+  
+## Related Sections  
+ [WPF Architecture](wpf-architecture.md)  
+  [XAML in WPF](xaml-in-wpf.md)  
+  [Element Tree and Serialization](element-tree-and-serialization.md)  
+  [Properties](properties-wpf.md)  
+  [Events](events-wpf.md)  
+  [Input](input-wpf.md)  
+  [Resources](resources-wpf.md)  
+  [Styling and Templating](/dotnet/desktop-wpf/fundamentals/styles-templates-overview)  
+  [Threading Model](threading-model.md)