CLN is a library for computations with all kinds of numbers. It has a rich set of number classes: - Integers (with unlimited precision), - Rational numbers, - Floating-point numbers: Short float, Single float, Double float, Long float (with unlimited precision), - Complex numbers, - Modular integers (integers modulo a fixed integer), - Univariate polynomials. The subtypes of the complex numbers among these are exactly the types of numbers known to the Common Lisp language. Therefore CLN can be used for Common Lisp implementations, giving `CLN' another meaning: it becomes an abbreviation of "Common Lisp Numbers".