Forging ..at least a loose interpretation .. is heating metal up & pounding on it. The process generally starts with a "billet" of steel. i.e. a chunk of steel only recognizable as that .. a chunk of steel. This is heated to a malleable state & literally pounded into a more recognizable state .. the desired end product. Could be a connecting rod for an engine .. could be a knife. In your case .. a knife. The rough but recognizable shape resulting from this hammering will be tempered and ground into the final form .. your son's forged knife. Generally speaking .. more time & pride goes into a forged unit. Your son most likely a knife he can cherish for a lifetime.

Hope that helped.