What does x: stand for in x:key and x:name ? Why the colon and why not y:?

Question

This is confusing to me. Why do we have to use x:Key= and x:Name= in place of key= and name=?

Where does this x come from?

Thanks!

Answer 1

The 'X' is an alias for an imported namespace (See the declaration of your XAML).

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

so when you type x, you use resources from that defined namespace. Actually, Name and Key are defined in the xaml namespace.

Answer 2

The name and key properties are defined within a namespace to avoid clashing with properties of the same name defined on the controls I believe.