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Including Header Files in C++
A C++ program can include header files. They are used to provide either an interface, which gives function prototypes for definition, or to provide pre-defined definitions.
//for standard system header files, like stdio.h. Will search standard system directories #include <file> //for header files built by the user, within the source code's directory #include "file"
These header files are included and compiled by the preprocessor.
#include <stdio.h> #include "myHeader.h"
Headers and Includes - C++ Forum