Code Hot-Reloading
Hot-reloading in the context of software refers to a program's ability to load-in modified versions of its resources mid-execution. This concept can extend to the programs own machine code when it supports code hot-reloading.
DLL-based Hot-Reloading
Hot-reloading of programs written in compiled languages like C or C++ can be achieved by loading in code from a dynamically linked library (DLL).
When this DLL changes on disk, the current DLL can be unloaded and the new DLL loaded.