In Unity, you normally use scripts to create functionality but you can also include code created outside Unity in the form of a Plugin. There are two kinds of plugins you can use in Unity: Managed plugins and Native plugins.
Managed plugins are managed .NET assemblies created with tools like Visual Studio or MonoDevelop. They contain only .NET code which means that they can’t access any features that are not supported by the .NET libraries. However, managed code is accessible to the standard .NET tools that Unity uses to compile scripts. There is thus little difference in usage between managed plugin code and Unity script code, except for the fact that the plugins are compiled outside Unity and so the source may not be available.
_原生插件_是特定于平台的本机代码库。此类插件可访问操作系统调用和第三方代码库等功能；Unity 无法通过其他方式使用这些功能。但是，Unity 的工具无法以托管库的方式访问这些库。例如，如果忘记将托管插件文件添加到项目中，您将收到标准编译器错误消息。如果也忘记将原生插件添加到项目中，则只会在尝试运行项目时看到错误报告。
This section explains how to create plugins and use them in your Unity projects.