说明：  Simple DirectMedia Layer库，简称 SDL，是为数不多的商业游戏开发公司使用的免费软件库之一。它提供跨平台的二维帧缓冲区图形和音频服务，它支持 Linux、Win32 和 BeOS。也不同程度地支持其它平台，包括 Solaris、IRIX、FreeBSD 和 MacOS。除了大量的服务，包括线程、独立于字节存储次序的宏和 CD 音频，SDL 还提供了一个简单的 API，它允许您尽可能接近本机硬件。使用 SDL 有三重优点：稳定、简单和灵活。
(Simple DirectMedia Layer library, or SDL, is one of the few commercial game development company uses one of the free software library. It provides two-dimensional cross-platform graphics frame buffer and audio services, it supports Linux, Win32 and BeOS. To varying degrees, also support other platforms, including Solaris, IRIX, FreeBSD and MacOS. Apart from a large number of services, including threads, independent of the byte storage order of the macro and CD audio, SDL also provides a simple API, it allows you as close as possible to the local hardware. The use of SDL has three advantages: stable, simple and flexible.)