Can someone please explain to me these codes?

[iamalem]

include<stdlib.h>
#include<unistd.h>
#include<sys/wait.h>
#include<iostream>
using std::cout;
using std::endl;
main()
{
int usaid;
int status;
cout<<endl<<endl;
cout<<'/a'<<"Process A has begun executing"<<endl;
cout<<"it's PID is "<<getpid()<<endl;
cout<<"Process A will wait for its children to exit"<<endl<<endl;
wait(&status);
sleep(10);

pid_t B=fork();
if(B==0)
{
cout<<'/a'<<"Process B has begun executing"<<endl;
cout<<"It's PID is "<<getpid()<<endl;
cout<<"it's PPID is "<<getppid()<<endl;
cout<<"Process B will now exit"<<endl<<endl;
exit(B);
}
exit(0);
return 0;
}

[bibblebub]

All the cout lines are just sending characters to the output stream.

The main program displays that it has started etc., then spawns a copy of itself and displays a message if that is successful, and finally terminates that clone before terminating itself..

[bibblebub]

^^^ forget the terminating part of that answer, it's been years since I've written code.