IL2CPP is a Unity-developed scripting back-end which you can use as an alternative to Mono when building projects for some platforms. When you choose to build a project using IL2CPP, Unity converts IL code (sometimes called CIL - Intermediate Language or Common Intermediate Language) from scripts and assemblies into C++ code, before creating a native binary file (.exe, apk, .xap, for example) for your chosen platform. Some of the uses for IL2CPP include increasing the performance, security, and platform compatibility of your Unity projects.
有关使用 IL2CPP 的更多信息，请参阅 Unity IL2CPP 博客系列和以下 Unity 手册页。
Note - IL2CPP is only available when building for the following platforms:
*IL2CPP is the only scripting back end available when building for iOS and WebGL.
• 2017–05–16 Page amended with no editorial review