The previous seven chapters describe the C++ language. This and the next two chapters describe the library. The library consists of a number of headers, in which each header declares types, macros, and functions for use in C++ programs. Much of the standard library is implemented using templates, so the implementation is typically embodied entirely in header files. Nonetheless, parts of the library are separately compiled and must be linked into a C++ program, the details of which are dictated by the implementation.
This chapter presents an overview of the standard library and some of its more important components: wide and multibyte characters, traits, policies, allocators, and numerics. Other important parts of the library get their own chapters: Chapter 9 introduces the input and output classes, and Chapter 10 describes the containers, iterators, and algorithms that make up what is most often known as the “standard template library,” or STL.