Like many culinary terms, "veal" came to English from French. It refers to the meat of a young cow, or calf, as opposed to "beef" (also from French), an adult cow's meat.
Prized for its tenderness and delicate flavor, veal has appeared in the cuisines of Italy, France and Germany for centuries. It dates back to (at least) Roman times, when Emperor Alexander Severus outlawed calf slaughter due to overconsumption.
The different varieties of veal depend on the calves' diet. "Milk-fed" calves (actually raised on a milk-like supplement) produce a pale pink veal, while "grain-fed" calves produce redder, fattier meat.
Veal production has prompted strong criticism from animal welfare groups. Traditional practices place calves in small (30 by 70 inch) individual crates that prevent much movement; most calves aren't able to turn around. By depriving the animals of exercise, veal producers aim to reduce muscle growth, keeping the meat tender. Calves spend only a few hours or days with their mothers before moving to crate confinement, where they live for 12 to 23 weeks before being slaughtered.
In response to animal rights advocacy, several countries and U.S. states have outlawed the use of crates for veal production, and the American Veal Association has committed to ending the practice by 2017.