@Meean, milk directly taken from cow and used immediately can termed as whole milk on which no processing whatsoever has been done. Whereas the milk that we normally get in the form of packets or bottles has been pasteurized. Pasteurization, the process named after Louis Pasteur, is carried out to reduce the number of viable pathogens in milk so they are unlikely to cause any diseases. Another variety of milk in packets now availble is skimmed milk, wherein fats are removed from milk so that the milk contains less calories. Trust this is helpful to you.