Box Object

The Box object is used to group components of an equation, to apply a single property to everything in the box. The Box serves a number of distinct purposes, including grouping characters to form a single operator (an operator emulator), and thereby inheriting the alignment and manual break properties of operators; grouping a differential such as ; preventing line breaks from occurring within; and allowing text inside to be reduced in script level.

An example of a Box serving as an operator emulator is: