From Wikipedia:

"Simple DirectMedia Layer (SDL) is a cross-platform multimedia free software library written in C that creates an abstraction over various platforms' graphics, sound, and input APIs, allowing a developer to write a computer game or other multimedia application once and run it on many operating systems including GNU/Linux, Windows and Mac OS X. It manages video, events, digital audio, CD-ROM, sound, threads, shared object loading, networking and timers."

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