Dart code can be run in a Dart-capable environment. A Dart-capable environment provides essential features to an app, such as the following:

• Runtime systems
• Dart core libraries
• Garbage collectors

The execution of Dart code operates in two modes—Just-In-Time (JIT) compilation or Ahead-Of-Time (AOT) compilation:

• A JIT compilation is where the source code is loaded and compiled to native machine code by the Dart VM on the fly. It is used to run code in the command-line interface or when you are developing a mobile app in order to use features such as debugging and hot reloading.
• An AOT compilation is where the Dart VM and your code are precompiled and the VM works more like a Dart runtime system, providing a garbage collector and various native methods from the Dart software development kit (SDK) to the application.