A fox is about the size of a small dog. It has amazing senses. Its ears can pick up the squeak of a mouse buried under snow. Its nose can smell food from hundreds of metres away. Its eyes have a reflective layer at the back that makes them shine yellow in torchlight - that's the same trick cats and many night animals use.
Foxes are 'omnivores' - they eat almost anything. In the countryside they hunt mice, voles and rabbits, and they also love berries, beetles and worms. In cities they have learned to live alongside people, eating leftovers from bins and snoozing under garden sheds.
Baby foxes are called 'cubs' or 'kits'. They are born in early spring, deep inside a den that the parents have dug in soft soil. The mother stays with them at first while the father brings food. By summer the cubs come out to play - rolling around in the grass exactly like puppies.
Foxes are mostly quiet, but at night you can sometimes hear them. The eerie scream you might hear in a British garden in winter is usually a fox calling to find a mate. It sounds a bit like someone shouting and is one of the strangest noises in British wildlife.