Core is a file created by the operating system when a program terminates unexpectedly, due to a bug, or a violation of the operating system's or hardware's protection mechanisms. The operating system kills the program and creates a core file that programmers can use to figure out what went wrong. It contains a detailed description of the state that the program was in when it died. Core, core file, core dump are the same thing.
int main()
{
int lIntegers[100000000];
int lInteger = 0;
int *lpInteger = 0;
*lpInteger = lInteger;
}