But if you run this you will get a rude Segmentation fault. We cannot actually modify pointer_to_number because, even if it is a location of memory that contains an address (and it would contain another address after the store) it is not in the data section, but in the text section. So this is a statically defined pointer, whose value (i.e. the address it contains) cannot change. So, how can we have a pointer that can change? Well, we will have to put it in the data section, where we usually put all the data of our program.