3 files = 1 program HELP!!!!

Im very n00b to programming and im working on this project..... and
I've got 3 different files....a header file ('file.h'), an
Implementation file ('file.cpp') and a driver file ('driver.cpp'). In
both the file.cpp and driver.cpp files..i put #include "file.h" ...but
im pretty sure thats wrong...i mean how does the driver file know how
to include my "file.cpp" implementaion file?? HELP THIS plz
tx...