linker « include « C File Q&A

1. Linking object files, making include redundant?    stackoverflow.com

I am trying my hand at a bit of C. And I thought I had understood this linking business. But I guess not. I have a simple file main.c:

#include "function.h"
int main(char ...

2. How gcc linker works in including files    stackoverflow.com

This is really a newbie question. I'm learning C, and I don't understand how to link together different files. I have a header like

/* file2.h */

int increment(int x);

/* file2.c */

#include ...