Formats its content as an XML tag. The control is a simple example of what’s effectively a parameterized HTML macro that includes both content (opening and closing brackets) and styling (a fixed-width font).

The script defines the Tag control’s own contents to be as the contents of the span tag.

The behavior of the Tag control is simple enough that it could be replicated purely in CSS 3 by making use of the “content” attribute. The content attribute allows one to specify text that should appear before and after a matching HTML element. The QuickUI approach is more flexible in that it allows arbitrary elements to be placed before and after the control’s content.