It's clear that all <xen: tags have been created for the purposes of making a developer's life easier, yet not all <xen: tags can be used in all types of template. In the Admin Templates although you can use tags such as: <xen:radiounit> <xen:hint> <xen:option> <xen:textbox> <xen:spinbox> and many more... You can't do the same in public templates. If I wanted to produce this: In an admin template this takes 8 lines of code. In a public template, the exact same thing takes 32 lines of code. Although these elements aren't widely used in public templates, they can still be useful. Especially for add-on developers.