A young male pig is called a piglet. When it weighs between 25 to 40 pounds, it is called a weanling. Boar refers to a young, uncastrated male pig.
Hog is the name given to a castrated male pig. If it was castrated before puberty, it is called a barrow.
A pig is the domesticated version of a wild boar. It usually has a huge head and a long snout, which is an acute sense organ. A pig uses its snout for digging into the soil for food. Pigs are omnivores. They eat plants, grass, worms, small animals and insects. Pigs are reared in farms for commercial purposes.