The problem comes when the icon that it defaults to for printing is a right load, but the only way that envelopes can be loaded is in the center of the tray. I have an HP Colorlaserjet 3600 and an HP Officejet Pro 8600 and both load this way.
A technical definition of a function is: a relation from a set of inputs to a set of possible outputs where each input is related to exactly one output.
domain of a function - (mathematics) the set of values of the independent variable for which a function is defined. domain. math, mathematics, maths - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement.