- GameSounds.xyz - Royalty free music and sounds. Various licenses, including free ones.
- CC0 Music - A collection of music. CC0.
- Creative Commons on SoundCloud - A Creative Commons collection on SoundCloud. Various licenses, all CC.
- Jamendo - A site providing music licensed under the Creatives Commons. Various licenses, all CC.
- jsfxr - A tool like sfxr-sdl but in ECMAScript. Unlicense.
- sfxr-sdl - A tool to generate sounds. Expat.
- SoundBible's Royalty-free section - A collection of CC or public-domain-licensed sounds. CC or public domain.
- AGS - Implemented in C++. Scripted using its own scripting language. Designed for adventure games. Artistic License 2.0.
- AlephOne - Implemented in C++. Designed for FPS games. GNU GPLv3 or later.
- AnKi 3D - Implemented in C++. 3-clause BSD.
- Castle Game Engine - Implemented in ObjectPascal. GNU LGPLv2 or later.
- HERITAGE - Implemented in ECMAScript. Designed for text adventure games. GNU GPLv3 or later.
- ioquake3 - Implemented in C. A fork of the Quake III Arena engine. GNU GPLv2 or later.
- Irrlicht - Implemented in C++. Has a range of bindings. zlib.
- JNGL - Implemented in C++. Designed for 2D games. zlib.
- Ogre3D - Implemented in C++. Has a range of bindings. Expat. Has custom plotscript language for advanced scripts. An oldschool RPG Maker alternative. GNU GPLv2 or later.
- Oxygine - Implemented in C++. Expat.
- Panda3D - Implemented in C++. Has a Python interface. 3-clause BSD..
- SGE - Implemented in Python. Designed for 2-D games. GNU GPLv3 language. GNU LGPLv3 only with the GTK Dev Kit GNU GPLv3 or later.
- Solarus - Implemented in C++. Has a Lua API and game editor. Designed for Action-RPGs. GNU GPLv3 or later.
Unless stated otherwise, these engines are implemented in ECMAScript.
- Box2D - Implemented in C++. Designed to simulate rigid body physics. zlib.
- LiquidFun - LiquidFun is a 2D rigid-body and fluid simulation C++ library for games based upon Box2D. zlib.
- Matter.js - Implemented in ECMAScript. Physics engine for HTML5. Expat.
- Oimo.js - Implemented in ECMAScript. Expat.
- Rapier - Fast 2D and 3D physics engine for the Rust programming language. Apache2.0
- Craft - A 3D voxel world game. Expat (code and assets).
- The Legend of Edgar - A 2D platform game with a persistent world. GNU GPLv2 or later (code), various free culture licenses (assets).
- Taisei - Expat (code and assets), OFL only for one font.
- Blackvoxel - A voxel exploration and crafting game. GNU GPLv3 or later (code and assets).
- SuperTuxKart - A 3D racing game. GNU GPLv3 or later (code), various free licenses (assets).
- Warzone 2100 - An RTS sci-fi game. GNU GPLv2 or later (code), various free culture licenses (assets).
- Cataclysm: Dark Days Ahead - A roguelike set in a post-apocalyptic world. CC-BY-3.0 (code), CC-BY-SA-3.0 (assets).
- DynaDungeons - A version of Bomberman. Uses Godot engine. GNU GPLv3 or later (code), various CC (no NC or ND) (assets).
- Tanks of Freedom - Pixed-based turn-based strategy. Uses Godot engine. Expat (code and assets).
- Teeworlds - Implemented in C and C++. 3-clause BSD (code), CC-BY-SA-3.0 (assets).
- Hexoshi - Free-roaming Metroid-like. GNU GPLv3 only (code), various CC (no NC or ND) (assets).
- Mystic Mine - Expat (code and assets).
- ReTux - A platformer. GNU GPLv3 only (code), various free culture licenses (assets).
- RogueBox Adventures - A mix of classical roguelike and sandbox game. GNU GPLv3 or later (code), various free culture licenses (assets).
- Unknown Horizons - A real-time strategy simulation game.
- Blend Swap - A community of Blender artists and their work. Various licenses, all CC.
- mocapdata.com - A library of motion capture data. Various licenses, including free ones.
- Poly Pizza - Thousands of free low poly 3D models licensed under CC0 and CC-BY-3.0
- Free stuff by 7Soul1 - A collection of various game-related assets. Available in PNG. Public domain.
- Remastered Tyrian graphics - A collection of pixel spreadsheets for a top-down shooter. CC0.
- Synfig Studio - A 2D animation tool. GNU GPLv2 or later.
- FLIF - Reference implementation of the Free Lossless Image Format. Comes with additional tools. GNU GPLv3 only.
- pngquant - A command-line utility for lossy compression of PNG images. Has various front-ends available. FreeBSD.
- Material Maker - Procedural texture generation tool for use with PBR engines. Expat.
- Sproxel - A 3D interface for quickly editing and creating voxel-based 3D models. 3-clause BSD.
- School of Game Design, Wikiversity - A collection of learning resources for would-be game designers. CC-BY-SA-3.0.
- Blender 3D: Noob to Pro - A Wikibook for learning how to make 3D graphics with Blender. CC-BY-SA-3.0.
- Procedural Content Generation Wiki - A collection of articles about the use of procedural generation to make stuff in games. CC-BY-SA-3.0.
- Computer Science section on Saylor Academy - A collection of computer science courses. Many of these deal with useful concepts for game programming. CC-BY-3.0.
- Effective Go - A guide to writing good, clean and readable Go code for beginners. CC-BY-3.0 (text), 3-clause BSD (code).
- Functional Programming in JavaScript (video) - A series of tutorials about functional programming concepts, illustrated using ECMAScript. CC-BY-3.0.
- Lua Programming - A completed Wikibook on programming Lua. CC-BY-SA-3.0.
- Practical Haskell - getting started with Stack - A series of tutorials designed to help people get started programming Haskell. CC-BY-SA-4.0.
- pygame_stuff - A collection of code samples using PyGame. GNU GPLv3 or later.
- The GNU C Programming Tutorial - An introduction to programming in C by the nice GNU people. PDF. GNU FDL.
- Mostly adequate guide to functional programming (in JavaScript) - A book on the fundamentals of functional programming in ECMAScript. CC-BY-SA-4.0.
- Structure and Interpretation of Computer Programs - A classic programming and teaching text. Designed for teaching Scheme, but can be useful to anyone writing in any language. CC-BY-SA-4.0.
These are collections of game development-related talks, podcasts etc. that might be interesting or informative to people seeking to design games.
- Composers Play (podcast) - Listen to a video game composer discuss soundtracks of iconic games such as Mass Effect, Duke Nukem II, Doom, and System Shock with their composers, often while playing the game.
- GameDevRadio (podcast) - A series of online radio shows devoted to entertaining and educating whoever is interested in game development. CC-BY-SA-4.0.
- Indievelopment talks (video) - A collection of talks about various aspects of game development. CC0.
These are programming libraries or low-level code-based tools which are designed to support game programming, but do not provide as much structure or support as an engine would.
- ActionKid - A simple video game framework. Implemented in Haskell. 3-clause BSD.
- Allegro 5 - A cross-platform library for low-level tasks, like creating windows, accepting user input and so forth. Implemented in C and C++. 3-clause BSD.
- bgfx - A 'build-your-own-engine' rendering library. FreeBSD.
- Chipmunk2D - A fast and lightweight 2D game physics library. Implemented in C. Expat.
- ChipmunkSharp - Advanced physics engine library based on Chipmunk. Implemented in C#. Expat.
- Cinder - A community-developed library for creative coding. Implemented in C++. FreeBSD.
- ClanLib - A cross-platform toolkit with a primary focus on game creation. Implemented in C++. (git). zlib.
- CutJS - A lightweight and fast 2D HTML5 rendering engine for cross-platform game development. Implemented in ECMAScript. Expat.
- Dear ImGui - An Immediate Mode Graphical User interface for C++ with minimal dependencies. zlib
- DotRecast - A port of Recast & Detour, navigation mesh toolset for games, Unity3D, servers, C#. zlib.
- enchant.js - A framework for developing simple HTML5 + ECMAScript games. Implemented in ECMAScript. Expat.
- EndGate - A framework for building HTML5 games. Implemented in TypeScript. Expat.
- Epoxy - A library for handling OpenGL function pointer management. Implemented in C. Expat.
- FNA - A reimplementation of the Microsoft XNA Game Studio 4.0 Refresh libraries. Implemented in C#. MS-PL
- Foster - A small cross-platform 2D game framework. Implemented in C#. MIT
- GameJs - A thin library on top of the Canvas API, including some helpful game development modules. Expat.
- Gideros - A cross-platform game development framework in Lua. Various licenses, all free.
- Gladiator3D - A raycasting engine. Implemented in ECMAScript. Expat.
- GLFW - A multi-platform library for OpenGL, OpenGL ES and Vulkan development on the desktop. zlib
- HaxeFlixel - A cross-platform development framework, supporting many targets. Implemented in Haxe. Expat.
- HaxePunk - A development framework designed to let you build games on any platform. Expat.
- ImGuizmo - An immediate mode 3D gizmo for scene editing and other controls based on Dear ImGui. MIT
- Kcp - A fast and reliable ARQ protocol that helps fast-action games reduct network latency. MIT
- Kuko - A cross-platform development library, designed for mobile devices. Implemented in C++ and Lua. Expat.
- LimeJS - A framework for building fast HTML5 games. Implemented in ECMAScript. Apache 2.0.
- LoomSDK - A very large and powerful framework for cross-platform 2D game development. Implemented in C++. Apache 2.0.
- LuaStudio - A cross-platform framework/development tool for making 2D/3D games. Lua/LuaJIT programming language based. zlib
- MINX - MINX Is Not XNA; a framework resembling XNA. Implemented in C++. 3-clause BSD.
- Polycode - Framework for games and interactive applications. Implemented in C++. Has Lua bindings. Expat.
- Quasi-Engine - A set of Qt-based tools for game development. Implemented in C++. GNU LGPLv2 or later.
- raylib - Low-level library designed to learn videogames programming. Implemented in C, but has Lua and Go bindings. zlib
- Slick2D - A set of tools to make 2D game development easier. Implemented in Java. 3-clause BSD.
- Tracy - C++ frame profiler. 3-clause BSD.
- ZenGL - A cross-platform game development library designed to provide necessary functionality for rendering 2D-graphics, handling input, sound output, etc. Implemented in Pascal. zlib.
This is a catch-all category for things that don't fit anywhere else.
- Assimp - Open Asset Import Library; a portable way to import various well-known 3D model formats in a uniform manner. Implemented in C++, with a range of bindings. 3-clause BSD.
- Easel.js - Provides a range of tools to make working with the HTML5 Canvas API easier. Implemented in ECMAScript. Expat.
- EnginesDatabase.com - A crowd-sourced database website of Game Engines and free (as in freedom) games for each engine.
- libnoise - A portable coherent noise-generation library. Implemented in C++. GNU LGPLv2 or later.
- TrenchBroom - A cross-platform level editor for Quake-engine-based games. Currently supports Quake, Quake 2 and Hexen 2 engine-based games. GNU GPLv3 or later.
- WorldForge - Provides everything needed to create your own free software MMORPG. GNU GPLv3 or later (or a compatible license).