Mode

Values are entered directly or indirectly. When values are entered directly, the compiler no longer needs to resolve the entry to get the actual value intended. When values are entered indirectly, the compiler still needs to resolve it either from the internal content document or the external content document associated with it, to get the actual value intended. This latter mode is what makes the document a true template.

Range

Values may come from an infinite range, a finite set, or boolean. From an infinite range, values are mostly are entered without or just a limited aid from the software. Aid could come from providing a dialog to search the actual value such as a filename. Alternatively, it offers a small subset of the most common values while allowing for the entry of a value outside the initial set. From a finite set, it offers all the available choices and rejects values outside of the closed set. A boolean is like the second with only two known choices, one affirmative and one negative.

Automacity

Attributes may have default values. They are entered automatically unless overriden by the user.