Open source games are even more open source if not only the source of the gameengine itself is available, but also all the other assets, such as sprites,samples, soundtracks et cetera also have their source available. What issource in the context of multimedia assets? And how can we create those assetsin a more source-like way? In this talk I will briefly point out the importance of source code, and whythis is also important for multimedia assets. I will show some file types, anddiscuss whether or not they are source, and if not what would be their source.Finally, I'll give a real example of creating music in the way a programmerwould write C or Python code, and compile the source of this music with amakefile into an Ogg Vorbis file. I hope this will bring more awareness aboutthe need for source code of multimedia to game developers, and hopefully itwill inspire others, including programmers that think they are not artistic,to create those assets, to share them, and to be able to learn from and modifythem.