Code Splitting → breaking down large code base into smaller, manageable files
Another benefit to code splitting is separate compilation: instead of source files being compiled in one go, they can be compiled into respective object files and then linked into executables or libraries. This means if a source file has not been updated, then the object file also does not need to be updated. Therefore, this can increase compilation time.
Header Files
Responsible for declaring classes, functions and variables needed by multiple source files.
You can think of them as defining the interface for other source files.
Source Files
Responsible for implementing the actual functionality defined in the corresponding header file.