Just-In-Time Compilation (JIT)

JIT (Just-In-Time Compilation) is a compilation process in which code is translated from an intermediate representation or a higher-level language (e.g., JavaScript or Java bytecode) into machine code at runtime, rather than prior to execution. This approach combines the benefits of both interpretation and ahead-of-time (AOT) compilation.

JIT compilers typically continuously analyze the code as it is executed, identifying parts of the code that are executed frequently (hot spots). If the speedup gains outweigh the compilation overhead, then the JIT compilers will compile those parts into machine code. The compiled code is then executed directly by the processor, which can result in significant performance improvements.