* [C++ Standard Library](http://en.wikipedia.org/wiki/C%2B%2B_Standard_Library) - A collection of classes and functions, which are written in the core language and part of the C++ ISO Standard itself.
* [Standard Template Library](http://en.wikipedia.org/wiki/Standard_Template_Library) - The Standard Template Library (STL).
* [ISO C++ Standards Committee](https://github.com/cplusplus) - ISO/IEC JTC1/SC22/WG21 - The C++ Standards Committee. [website](http://www.open-std.org/JTC1/SC22/WG21/)
* [Apache C++ Standard Library](http://stdcxx.apache.org/) - A collection of algorithms, containers, iterators, and other fundamental components. [Apache2]
* [ASL](http://stlab.adobe.com/) - Adobe Source Libraries provides peer-reviewed and portable C++ source libraries. [MIT]
* [BDE](https://github.com/bloomberg/bde) - The BDE Development Environment from Bloomberg Labs. [MIT]
* [Cinder](http://libcinder.org/) - A community-developed, free and open source library for professional-quality creative coding. [BSD]
* [Cxxomfort](http://ryan.gulix.cl/fossil.cgi/cxxomfort/) - A small, header-only library that backports to C++03 some of the nifty C++11 goodies. [MIT]
* [Dlib](http://dlib.net/) :star: - A general purpose cross-platform C++ library designed using contract programming and modern C++ techniques. [Boost]
* [JUCE](https://github.com/julianstorer/JUCE) - An all-encompassing C++ class library for developing cross-platform software. [Core-Module: ISC, Rest: GPL2/GPL3/Commercial] [website](http://www.juce.com/)
* [libPhenom](https://github.com/facebook/libphenom) - libPhenom is an eventing framework for building high performance and high scalability systems in C. [Apache2]
* [LibSourcey](https://github.com/sourcey/libsourcey) - C++11 evented IO for real-time video streaming and high performance networking applications. [LGPL]
* [LibU](https://github.com/koanlogic/libu) - A multiplatform utility library written in C. [BSD]
* [Loki](http://loki-lib.sourceforge.net/) - A C++ library of designs, containing flexible implementations of common design patterns and idioms. [MIT]
* [MiLi](https://code.google.com/p/mili/) - Minimal headers-only C++ Library. [Boost]
* [openFrameworks](http://www.openframeworks.cc/) - An open source C++ toolkit for creative coding. [MIT]
* [Reason](http://code.google.com/p/reason/) - A cross platform framework designed to bring the ease of use of Java, .Net, or Python to developers who require the performance and strength of C++. [GPLv2]
* [ROOT](http://root.cern.ch) - A set of OO frameworks with all the functionality needed to handle and analyze large amounts of data in a very efficient way. Used at CERN. [LGPL]
* [btsk](https://github.com/aigamedev/btsk) - Game Behavior Tree Starter Kit. [zlib]
* [Evolving Objects](http://eodev.sourceforge.net/) - A template-based, ANSI-C++ evolutionary computation library which helps you to write your own stochastic optimization algorithms insanely fast. [LGPL]
* [Neu](https://github.com/andrometa/neu) - A C++ 11 framework, collection of programming languages, and multipurpose software system designed for: the creation of artificial intelligence applications. [BSD]
* [Boost.Asio](http://think-async.com/) - A cross-platform C++ library for network and low-level I/O programming. [Boost]
* [libev](http://libev.schmorp.de/) - A full-featured and high-performance event loop that is loosely modelled after libevent, but without its limitations and bugs. [BSD and GPL]
* [libevent](http://libevent.org/) - An event notification library. [BSD]
* [FMOD](http://www.fmod.org/) - An easy to use crossplatform audio engine and audio content creation tool for games. [Free for non-commercial/Commercial]
* [Maximilian](https://github.com/micknoise/Maximilian) - C++ Audio and Music DSP Library. [MIT]
* [OpenAL](http://www.openal.org/) - Open Audio Library - A crossplatform audio API. [BSD/LGPL/Commercial]
* [PhysicsFS](https://icculus.org/physfs/) - A library to provide abstract access to various archives. It is intended for use in video games, and the design was somewhat inspired by Quake 3's file subsystem. [zlib]
* [KArchive](https://projects.kde.org/projects/frameworks/karchive) - A library for creating, reading, writing and manipulating file archives like zip and tar. It also provides transparent compression and decompression of data, using formats like gzip, via a subclass of QIODevice. [LGPL]
* [LZ4](https://code.google.com/p/lz4/) - Extremely Fast Compression algorithm. [BSD]
* [LZHAM](https://code.google.com/p/lzham/) - Lossless data compression library with a compression ratio similar to LZMA but with much faster decompression. [BSD]
* [LZMAT](http://www.matcode.com/lzmat.htm) - An extremely fast real-time lossless data compression library. [GPL]
* [miniz](https://code.google.com/p/miniz/) - Single C source file Deflate/Inflate compression library with zlib-compatible API, ZIP archive reading/writing, PNG writing. [Unlicense]
* [Minizip](https://github.com/nmoinvaz/minizip) - Zlib with latest bug fixes that supports PKWARE disk spanning, AES encryption, and IO buffering. [zlib]
* [Snappy](https://code.google.com/p/snappy/) - A fast compressor/decompressor. [BSD]
* [ZLib](http://zlib.net/) - A very compact compression library for data streams. [zlib]
* [ZZIPlib](http://zziplib.sourceforge.net/) - Provides read access on ZIP-archives. [MPL/LGPL]
* [C++ B-tree](https://code.google.com/p/cpp-btree/) - A template library that implements ordered in-memory containers based on a B-tree data structure. [Apache2]
* [Bcrypt](http://bcrypt.sourceforge.net/) - A cross platform file encryption utility. Encrypted files are portable across all supported operating systems and processors.
* [Tiny AES128 in C](https://github.com/kokke/tiny-AES128-C) - A small and portable implementation of the AES128 ECB encryption algorithm implemented in C. [PublicDomain]
* [RocksDB](https://github.com/facebook/rocksdb) - Embedded key-value store for fast storage from facebook. [BSD]
* [SQLite](http://www.sqlite.org/) - A completely embedded, full-featured relational database in a few 100k that you can include right into your project. [PublicDomain]
* [Cocos2d-x](http://www.cocos2d-x.org/) - A multi-platform framework for building 2d games, interactive books, demos and other graphical applications. [Commercial?]
* [Qwt](http://qwt.sourceforge.net/) - Qt Widgets for Technical Applications. [Own based on LGPL]
* [QwtPlot3D](http://qwtplot3d.sourceforge.net/) - A feature-rich Qt/OpenGL-based C++ programming library, providing essentially a bunch of 3D-widgets. [zlib]
* [OtterUI](https://github.com/Twolewis/OtterUI) - OtterUI is a User Interface development solution for embedded systems and interactive entertainment software. [MIT]
* [wxWidgets](http://wxwidgets.org/) - A C++ library that lets developers create applications for Windows, Mac OS X, Linux and other platforms with a single code base. [Own LGPL]
* [Ogre 3D](http://www.ogre3d.org/) :star: - A scene-oriented, real-time, flexible 3D rendering engine (as opposed to a game engine) written in C++. [MIT]
* [FreeImage](http://freeimage.sourceforge.net/) - An open source library that supports popular graphics image formats and others as needed by today's multimedia applications. [GPLv2 or GPLv3]
* [Recommender](https://github.com/GHamrouni/Recommender) - C library for product recommendations/suggestions using collaborative filtering (CF). [BSD]
* [SHOGUN](https://github.com/shogun-toolbox/shogun) - The Shogun Machine Learning Toolbox. [GPLv3]
* [sofia-ml](https://code.google.com/p/sofia-ml/) - The suite of fast incremental algorithms for machine learning. [Apache2]
* [Armadillo](http://arma.sourceforge.net/) - A high quality C++ linear algebra library, aiming towards a good balance between speed and ease of use. The syntax (API) is deliberately similar to Matlab. [MPL2]
* [blaze](https://code.google.com/p/blaze-lib/) - high-performance C++ math library for dense and sparse arithmetic. [BSD]
* [ceres-solver](http://ceres-solver.org/) - C++ library for modeling and solving large complicated nonlinear least squares problems from google. [BSD]
* [Eigen](http://eigen.tuxfamily.org/) - A high-level C++ library of template headers for linear algebra, matrix and vector operations, numerical solvers and related algorithms. [MPL2]
* [GMTL](http://ggt.sourceforge.net/) - Graphics Math Template Library is a collection of tools implementing Graphics primitives in generalized ways. [GPLv2]
* [GMP](https://gmplib.org/) - A C/C++ library for arbitrary precision arithmetic, operating on signed integers, rational numbers, and floating-point numbers. [LGPLv3 and GPLv2]
* [QtAv](https://github.com/wang-bin/QtAV) - A multimedia playback framework based on Qt and FFmpeg to write a player easily. [LGPL] [website](http://wang-bin.github.io/QtAV/)
* [Muduo](https://github.com/chenshuo/muduo) - A C++ non-blocking network library for multi-threaded server in Linux. [BSD]
* [net_skeleton](https://github.com/cesanta/net_skeleton) - TCP client/server library for C/C++. [GPLv2]
* [nope.c](https://github.com/riolet/nope.c) - A C language-based ultra-light software platform for scalable server-side and networking applications. Think node.js for C programmers. [GPLv2]
* [Onion](https://github.com/davidmoreno/onion) - HTTP server library in C designed to be lightweight and easy to use. [Apache2/GPLv2]
* [POCO](https://github.com/pocoproject) :star: - C++ class libraries and frameworks for building network- and internet-based applications that run on desktop, server, mobile and embedded systems. [Boost] [website](http://pocoproject.org/)
* [ODE](http://www.ode.org/) - Open Dynamics Engine - An open source, high performance library for simulating rigid body dynamics. [BSD&LGPL]
* [ofxBox2d](https://github.com/vanderlin/ofxBox2d) - openFrameworks wrapper for Box2D. [BSD-like]
* [Simbody](https://github.com/simbody/simbody) - High-performance C++ multibody dynamics/physics library for simulating articulated biomechanical and mechanical systems like vehicles, robots, and the human skeleton. [Apache2]
* [MOOS-IvP](http://moos-ivp.org) - A set of open source C++ modules for providing autonomy on robotic platforms, in particular autonomous marine vehicles.
* [MRPT](http://www.mrpt.org/) - Mobile Robot Programming Toolkit. [BSD]
* [PCL](https://github.com/PointCloudLibrary/pcl) - Point Cloud Library is a standalone, large scale, open project for 2D/3D image and point cloud processing [BSD] [website](http://www.pointclouds.org/)
* [ChaiScript](https://github.com/ChaiScript/ChaiScript/) - An easy to use embedded scripting language for C++. [BSD] [website](http://chaiscript.com/)
* [Lua](http://www.lua.org/) - A minimal and fast scripting engine for configuration files and basic application scripting. [MIT]
* [luacxx](https://github.com/dafrito/luacxx) - C++11 API for creating Lua bindings. [MIT]
* [SWIG](http://www.swig.org/) - A wrapper/interface Generator that let you link your c++ code to Javascript, Perl, PHP, Python, Tcl and Ruby. [GPL/Output not licensed]
* [SimpleBinaryEncoding](https://github.com/real-logic/simple-binary-encoding) - encoding and decoding application messages in binary format for low-latency applications. [Apache2]
* [Thrift](https://thrift.apache.org/) - Efficient cross-language IPC/RPC, works between C++, Java, Python, PHP, C#, and many more other languages. Originally developer by Twitter. [Apache2]
* [Civetweb](https://github.com/bel2125/civetweb) - Provides easy to use, powerful, C/C++ embeddable web server with optional CGI, SSL and Lua support. [MIT]
* [QDjango](https://github.com/jlaine/qdjango/) - A web framework written in C++ and built on top of the Qt library. Where possible it tries to follow django's API, hence its name. [LGPL]
*XML is crap. Really. There are no excuses. XML is nasty to parse for humans, and it's a disaster to parse even for computers. There's just no reason for that horrible crap to exist. - Linus Torvalds*
* [Expat](http://www.libexpat.org/) - An XML parser library written in C. [MIT]
* [Libxml2](http://xmlsoft.org/) - The XML C parser and toolkit of Gnome. [MIT]
* [libxml++](http://libxmlplusplus.sourceforge.net/) - An XML Parser for C++. [LGPLv2]
* [PugiXML](http://pugixml.org/) - A light-weight, simple and fast XML parser for C++ with XPath support. [MIT]
* [RapidXml](http://rapidxml.sourceforge.net/) - An attempt to create the fastest XML parser possible, while retaining useability, portability and reasonable W3C compatibility. [Boost]
* [TinyXML](http://sourceforge.net/projects/tinyxml/) - A simple, small, minimal, C++ XML parser that can be easily integrating into other programs. [zlib]
* [TinyXML2](https://github.com/leethomason/tinyxml2) - A simple, small, efficient, C++ XML parser that can be easily integrating into other programs. [zlib]
* [TinyXML++](https://code.google.com/p/ticpp/) - A completely new interface to TinyXML that uses MANY of the C++ strengths. Templates, exceptions, and much better error handling. [MIT]
* [Xerces-C++](http://xerces.apache.org/xerces-c/) - A validating XML parser written in a portable subset of C++. [Apache2]
* [Better String](http://bstring.sourceforge.net) - An alternative to the string library for C which is more functional and does not have buffer overflow overrun problems. Also includes a C++ wrapper. [BSD, GPLv2]
* [QtVerbalExpressions](https://github.com/VerbalExpressions/QtVerbalExpressions) - This Qt lib is based off of the C++ VerbalExpressions library. [MIT]
* [PHP-CPP](https://github.com/CopernicaMarketingSoftware/PHP-CPP) - A library to build PHP extensions with C++. [Apache2] [website](http://www.php-cpp.com/)
* [SLDR](https://github.com/cesanta/sldr) - Super Light DNS Resolver. [GPLv2/Commercial]
* [SLRE](https://github.com/cesanta/slre) - Super Light Regular Expression library. [GPLv2/Commercial]
* [Stage](https://github.com/rtv/Stage) - Mobile robot simulator. [GPLv2]
* [VarTypes](https://code.google.com/p/vartypes/) - A feature-rich, object-oriented framework for managing variables in C++ / Qt4. [LGPL]
* [ZBar](http://zbar.sourceforge.net/) - A barcode scanner library, which allows to scan photos/images/video streams for barcodes and return their value. [LGPLv2]
* [ZXing](https://github.com/zxing/zxing/) - An open-source, multi-format 1D/2D barcode image processing library implemented in Java, with ports to other languages. [Apache]
* [Microsoft Visual C++](http://msdn.microsoft.com/en-us/vstudio/hh386302.aspx) - MSVC, developed by Microsoft.
* [Open WatCom](http://www.openwatcom.org/index.php/Main_Page) - Watcom C, C++, and Fortran cross compilers and tools. [Sybase Open Watcom Public License]
* [TCC](http://bellard.org/tcc/) - Tiny C Compiler. [LGPL]
* [codepad](http://codepad.org/) - An online compiler/interpreter, and a simple collaboration tool.
* [CodeTwist](http://codetwist.com/) - A simple online compiler/interpreter, where you can paste your C, C++ or Java code and execute it online and see results.
* [CompileOnline](http://www.compileonline.com/compile_cpp11_online.php) - Compile and Execute C++ online on Linux.
* [Ideone](http://ideone.com/) - An online compiler and debugging tool which allows you to compile source code and execute it online in more than 60 programming languages.
* [CMake](http://www.cmake.org/) - Cross-platform free and open-source software for managing the build process of software using a compiler-independent method. [BSD]
* [tundra](https://github.com/deplinenoise/tundra) - High-performance code build system designed to give the best possible incremental build times even for very large software projects.
* [tup](http://gittup.org/tup/) - File-based build system that monitors in the background for changed files.
* [Premake](http://industriousone.com/premake) - A tool configured with lua scipt to generate project files for Visual Studio, GNU Make, Xcode, Code::Blocks, and more across Windows, Mac OS X, and Linux.
* [OCLint](http://oclint.org/) - A static source code analysis tool to improve quality and reduce defects for C, C++ and Objective-C. - [source](https://github.com/oclint/oclint)
* [Clang Static Analyzer](http://clang-analyzer.llvm.org/index.html) - A source code analysis tool that finds bugs in C, C++, and Objective-C programs.
* [List of tools for static code analysis](http://en.wikipedia.org/wiki/List_of_tools_for_static_code_analysis#C.2FC.2B.2B) - A list of tools for static code analysis from Wikipedia.
* [The C++ Annotations](http://cppannotations.sourceforge.net/annotations/html/) - An in-depth guide on C++, intended for people with a good knowledge of C who want to make the transition to C++.
* [The Definitive C++ Book Guide and List](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list) - A collection of quality books and an approximate skill level.
* [C++ Dos and Don'ts](http://www.chromium.org/developers/coding-style/cpp-dos-and-donts) - The Chromium Projects > For Developers > Coding Style > C++ Dos and Don'ts.
* [Awesome C Programming Tutorials in Hi Def [HD]](https://www.youtube.com/playlist?list=PLCB9F975ECF01953C) - A collection of detailed C Programming Language Tutorials for Beginners and New Programmers.
* [C++](https://www.youtube.com/playlist?list=PL2F919ADECA5E39A6) - by VoidRealms.
* [C++ Qt Programming](https://www.youtube.com/playlist?list=PL2D1942A4688E9D63) - by VoidRealms.
* [C++ Programming Tutorials from thenewboston](https://www.youtube.com/playlist?list=PLF541C2C1F671AEF6) - These are all of thenewboston's C++ programming tutorials.
* [C++ GUI with Qt Playlist](https://www.youtube.com/playlist?list=PLD0D54219E5F2544D) - Official Playlist for thenewboston C++ GUI with Qt tutorials.
* [ToolsOfTheTrade](https://github.com/cjbarber/ToolsOfTheTrade) - Tools of The Trade, from Hacker News.
* [cheatsheets.org](http://www.cheatsheets.org/) - The largest collection of reference cards for developers.
* [cheat-sheets.org](http://www.cheat-sheets.org/) - All cheat sheets, round-ups, quick reference cards, quick reference guides and quick reference sheets in one page.
* [thefreecountry.com](http://www.thefreecountry.com/) - A collection of free programming resources, free webmasters' resources, free security resources and free utilities.