Integer: The organization of boost integer headers and classes is designed to take advantage of <stdint.h> types from the 1999 C standard without resorting to undefined behavior in terms of the 1998 C++ standard. The header <boost/cstdint.hpp> makes the standard integer types safely available in namespace boost without placing any names in namespace std.

Value Initialized: Wrapper for uniform-syntax value initialization, based on the original idea of David Abrahams.

Python: The Boost Python Library is a framework for interfacing Python and C++. It allows you to quickly and seamlessly expose C++ classes functions and objects to Python, and vice-versa, using no special tools -- just your C++ compiler.

Iterator: The Boost Iterator Library contains two parts. The first is a system of concepts which extend the C++ standard iterator requirements. The second is a framework of components for building iterators based on these extended concepts and includes several useful iterator adaptors.

Math: Boost.Math includes several contributions in the domain of mathematics: The Greatest Common Divisor and Least Common Multiple library provides run-time and compile-time evaluation of the greatest common divisor (GCD) or least common multiple (LCM) of two integers. The Special Functions library currently provides eight templated special functions, in namespace boost. The Complex Number Inverse Trigonometric Functions are the inverses of trigonometric functions currently present in the C++ standard. Quaternions are a relative of complex numbers often used to parameterise rotations in three dimentional space. Octonions, like quaternions, are a relative of complex numbers.

Member Function: Generalized binders for function/object/pointers and member functions.

Bind: boost::bind is a generalization of the standard functions std::bind1st and std::bind2nd. It supports arbitrary function objects, functions, function pointers, and member function pointers, and is able to bind any argument to a specific value or route input arguments into arbitrary positions.

IO State Savers: The I/O sub-library of Boost helps segregate the large number of Boost headers. This sub-library should contain various items to use with/for the standard I/O library.

Lambda: Define small unnamed function objects at the actual call site, and more.

Multi-Array: Boost.MultiArray provides a generic N-dimensional array concept definition and common implementations of that interface.

Date Time: A set of date-time libraries based on generic programming concepts.

Dynamic Bitset: The dynamic_bitset class represents a set of bits. It provides accesses to the value of individual bits via an operator[] and provides all of the bitwise operators that one can apply to builtin integers, such as operator& and operator<<. The number of bits in the set is specified at runtime via a parameter to the constructor of the dynamic_bitset.

Format: The format library provides a class for formatting arguments according to a format-string, as does printf, but with two major differences: format sends the arguments to an internal stream, and so is entirely type-safe and naturally supports all user-defined types; the ellipsis (...) can not be used correctly in the strongly typed context of format, and thus the function call with arbitrary arguments is replaced by successive calls to an argument feeding operator%.

uBLAS: uBLAS provides matrix and vector classes as well as basic linear algebra routines. Several dense, packed and sparse storage schemes are supported.

MPL: The Boost.MPL library is a general-purpose, high-level C++ template metaprogramming framework of compile-time algorithms, sequences and metafunctions. It provides a conceptual foundation and an extensive set of powerful and coherent tools that make doing explict metaprogramming in C++ as easy and enjoyable as possible within the current language.

Multi-Index: The Boost Multi-index Containers Library provides a class template named multi_index_container which enables the construction of containers maintaining one or more indices with different sorting and access semantics.

Program Options: The program_options library allows program developers to obtain program options, that is (name, value) pairs from the user, via conventional methods such as command line and config file.

Assign: Filling containers with constant or generated data has never been easier.

Foreach: In C++, writing a loop that iterates over a sequence is tedious. We can either use iterators, which requires a considerable amount of boiler-plate, or we can use the std::for_each() algorithm and move our loop body into a predicate, which requires no less boiler-plate and forces us to move our logic far from where it will be used. In contrast, some other languages, like Perl, provide a dedicated "foreach" construct that automates this process. BOOST_FOREACH is just such a construct for C++. It iterates over sequences for us, freeing us from having to deal directly with iterators or write predicates.

TR1: The TR1 library provides an implementation of the C++ Technical Report on Standard Library Extensions. This library does not itself implement the TR1 components, rather it's a thin wrapper that will include your standard library's TR1 implementation (if it has one), otherwise it will include the Boost Library equivalents, and import them into namespace std::tr1.

Xpressive: Regular expressions that can be written as strings or as expression templates, and which can refer to each other and themselves recursively with the power of context-free grammars.

System: Operating system support, including the diagnostics support that will be part of the C++0x standard library.