This chapter discusses the various types of objects that can be placed on the Calculator stack, how they are displayed, and how they are entered. (See section Data Type Formats, for information on how these data types are represented as underlying Lisp objects.)
Integers, fractions, and floats are various ways of describing real numbers. HMS forms also for many purposes act as real numbers. These types can be combined to form complex numbers, modulo forms, error forms, or interval forms. (But these last four types cannot be combined arbitrarily: error forms may not contain modulo forms, for example.) Finally, all these types of numbers may be combined into vectors, matrices, or algebraic formulas.