Could someone please clear up the confusion?!
Red meat includes those meats that are dark in color before cooking. E.g. beef, lamb, venison, bison. These meats contain more myoglobin than white meats like poultry and fish. Pork is also considered red meat by the USDA because it is red before cooking (also due to high amounts myoglobin). However, it has been advertised as "the other white meat" in an attempt to make it seem healthier.
Red meat and white meat are not scientific labels, they are marketing words.
Red meat tends to contain a lot of myoglobin and be what are called slow twitch muscles. White meat tends not to have myoglobin and is called slow twitch muscles. Think of chicken, the white meat has to move fast to get the chicken to fly (if it could) and the muscles that do slow work like standing tends to be darker.
Nutritionists tend to characterize pork as red meat because it has many of the same nutritional characteristics, such as fat content, cholesterol, etc.
it was a marketing decision by the pork industry to show it as a healthier choice than beef.