Maybe one of the first things to learn about pointers; do not dereference NULL pointers. However, it is
a good idea to understand why it is a bad idea.
Anytime a standard library function is invoked, it might not be able to successfully perform its work. Malloc is no
exception & will return NULL if it was unable to allocate memory on your behalf. It is therefore important to always
verify the return value of malloc before assuming the pointer is usable.