Can you explain how Android Runtime works and how it ensures application execution?

Android Runtime (ART) is the environment for running applications on Android, replacing Dalvik VM. ART is responsible for executing the bytecode of applications compiled from Java or Kotlin.

Main stages of ART operation:

1. Ahead-of-Time (AOT) Compilation: When installing an application, ART compiles bytecode into machine code, which speeds up the startup and operation of the application.
2. Memory Management: ART uses a garbage collector for automatic memory management, freeing unused objects.
3. Optimization: ART applies various optimizations during compilation and execution, improving performance.

Thus, ART provides efficient application execution, reducing CPU load and speeding up startup compared to the previous Dalvik VM.