What is the difference between a stackpanel and a virtualizingstackpanel in WPF?

Question

What is the difference between a stackpanel and a virtualizingstackpanel in WPF?

Answer 1

This is to do with the visual tree. The virtualizingstackpanel works with things like list boxes etc to reduce the size of the visual tree by only displaying visible items - this is useful where databinding is taking place.