SML is an influential programming language that represents many state-of-the-art aspects of language design in a form usable for everyday programming. The language is in use worldwide, with applications ranging from network communication to theorem proving. This book serves as the definition for SML's standard library. It provides concise descriptions of the types and functions defined in the library. It also presents more extensive discussions on the design and use of the library.This manual will be an indispensable reference for students, professional programmers, and language designers.