Owls have been made popular in the last 20 years thanks to the success in popular culture such as the Harry Potter series and other works of fiction, and as a result are commonly associated with magic and mystery, as well as qualities such as beauty and wisdom. There are about 200 different species of owl in the world, with there being two different families; true owls and barn owls. Barn owls can be recognised by their heart shaped faces whereas true owls, of which there are almost 190 species, fall into the category of more rounded faces and larger heads so making them easy to spot and differentiate. No matter how graceful these animals can seem in fiction they are still ruthless predators, known for swooping down and snatching their prey from the ground and flying off again in the blink of an eye. Owls feed on small animals such as mice, rabbits and even squirrels and swallow them whole, regurgitating them later on in the form of pellets of bone and fur and other things that their stomachs wont digest. Most owls hunt during the night and are nocturnal, however there are a few species which do hunt and are awake during the day such as burrowing owls, adding more to the mystique of owls as people rarely see them in the wild during the day. Another well-known feature of owls are their ability to rotate their heads as much as 270 degrees, but not many people know exactly why this is necessary. Owls have this ability because their eyes are fixed in their eye sockets to ensure near perfect vision which helps them to see well in the dark when hunting. Their extraordinary hearing also helps them to hunt with their ears located just behind their eye sockets and are concealed by feathers.