Positioning Elements with Layout Properties

HorizontalAlignment property has values of Left, Center, Right, Stretch
VerticalAlignment property has values of Top, Center, Bottom, Stretch

When Width and Height properties are set, the element will not grow or shrink:

Margin

Margin="<Left Top Right Bottom>"
Margin="50" results in a margin of 50 pixels on all sides.
Margin="50 10" results in 50 pixels for left and right margins and 10 pixels for top and bottom margins.