#include

#include This directive is used to include header files in your program. There are two ways to use it:

#include <iostream>  // For standard library headers
#include "myheader.h"  // For your own headers

difference between <> and "" while including a header

For including header files using `<>`

All header files, either available in standard/system or inside include folder of CPP project can be included using <>

Even <iostream> file is same as C's <studio.h> i.e. it appends .h, designers of CPP decided to not mark them with <iostream.h> extension, maybe to differentiate CPP header files from C header file.

For including header files using `""`

This type of import we can used for module local header files, if a header file is only applicable to your project at a single place or just that folder, you can create a header file locally and import it as #include<myheader.h>

You can learn more about why we need header files in the first place here.