Managed Code is a type of code that is created to use the functionalities of a controlled runtime environment, such as the CLR (Common Language Runtime) in the .NET Framework. Instead of being directly performed by the operating system, it is always implemented by the controlled runtime environment. The controlled runtime environment provides a lot of features, for instance, garbage collection, handling of exceptions, type CHECKING, bounds checking, and other services to programs without requiring the intervention of the user. It also allocated MEMORY to the code, type safety, and other features. Applications built-in languages such as Java, VB.Net, and many others are always aimed at runtime environment services to manage execution, and programs CODED in these languages are referred to as managed code.

In the scenario of the .NET Framework, the compilation of the managed code is always done by the compiler in MSIL (Microsoft INTERMEDIATE Language) before creating an executable. The CLR's Just In Time (JIT) Compiler translates the intermediary language into native code that is particular to the architecture lying beneath when the programmer runs the executable. This procedure is running in a managed runtime execution environment, and the environment is in charge of the code's FUNCTIONALITY. The managed code is executed as indicated in the image below, with the source code coded in any .NET Framework language.

Because managed code is compiled into an intermediate language, the JIT compiler turns this intermediate language into architecture-specific instructions, providing platform independence.