With such a topic so broad we truly try to cover the basics from all angles in this group. Nothing too big or too small. Nutrition is as significant if not more as exercise is to reaching your goals so learn all you can.
If your abs aren't hard, that means that there is still a layer of fat covering them and making them fat. They will turn "hard" after enough of the fat is burned. I think whenever you see six indentions in your abdominal area, it's considered a six pack.
Might not be well defined, but still a six pack.