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copied!<p>When you write</p> <pre><code><Label name="myLabel" Content="{Binding Path=Name}" /> </code></pre> <p>you are binding to <code>myLabel.DataContext.Name</code>, and not <code>myLabel.Name</code>.</p> <p>The XAML in WPF is just a pretty user interface to display and interact with the actual data, otherwise known as the <code>DataContext</code>. The purpose of other binding sources (<code>RelativeSource</code>, <code>ElementName</code>, etc) is to point to another property that doesn't exist in the current control's <code>DataContext</code> <hr> So suppose you have a Window. Without setting the DataContext, the window still displays but there is no data behind it.</p> <p>Now suppose to set <code>myWindow.DataContext = new ClassA();</code>. Now the data that the window is displaying is <code>ClassA</code>. If <code>ClassA</code> has a property called <code>Name</code>, I could write a label and bind it to <code>Name</code> (such as your example), and whatever value is stored in <code>ClassA.Name</code> would get displayed.</p> <p>Now, suppose <code>ClassA</code> has a property of <code>ClassB</code> and both classes have a property called <code>Name</code>. Here is a block of XAML which illustrates the purpose of the DataContext, and an example of how a control would refer to a property not in it's own DataContext</p> <pre><code><Window x:Name="myWindow">  <StackPanel>   <Label Content="{Binding Name}" />  <StackPanel DataContext="{Binding ClassB}">  <Label Content="{Binding Name}" />  <Label Content="{Binding ElementName=myWindow, Path=DataContext.Name}" /> </StackPanel> </StackPanel> </Window> </code></pre> <p>As you can see, the DataContext is based on whatever data is behind the UI object.</p> <p><strong>Update:</strong> I see this question so often from new WPF users that I expanded this answer into a post on my blog: <a href="http://rachel53461.wordpress.com/2012/07/14/what-is-this-datacontext-you-speak-of/" rel="noreferrer">What is this “DataContext” you speak of?</a></p>

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