Difference between memmove and memcpy

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char* argv[]) {
    char str[] = "Start stop";
    
    printf("%s\n", str);
    
    memmove(str, str + 2, 3 * sizeof(char));
    // memcpy(str, str + 2, 3 * sizeof(char));
    
    printf("%s\n", str);
    
    return 0;
}