update images and vs article

Author: didiyordanova

controls/tabview/images/header-position.png

@@ -15,9 +15,11 @@ The TabView uses a set of visual elements when rendered.
 
 ## Displayed Elements
 
-- **Header area**—The area with the TabView header. The Header holds all TabView header items.
-- **Header items**—The TabView header items.
-- **Content area**—The content area corresponding to each header item.
+- **TabView Header**—The area that holds all TabView header items.
+- **Header Item**—The item that represents single header item of the `TabViewItem`.
+- **Header Text**—The text inside the header item.
+- **Selected Item**—The selected tab item. The header item background color changes and the content of the corresponding header item that is selected.
+- **TabView Content**—The content area corresponding to each header item.
 
 ## See Also