A boar is the male of many species, like a bear, a raccoon, and others, but is usually applied to the wild swine, which is called the Wild Boar. Here is the photo from Wikipedia and the writeup: Wild boar. read more
Ironing out the differences between the varieties of swine may seem complicated, because many pig-related terms are used interchangeably. We could walk a pig-like animal into a room of people, ask them what the animal is, and get a wide range of responses, including pig, hog, boar, or swine. read more
In general, pig is a hog and a hog is a pig. The two terms can be used interchangeably for any adult of Sus scrofa domestica, the familiar barnyard animal. In the animal world, special words often are used to describe gender, age and reproductive status. read more