Frogs have bilateral symmetry. Most animals, including humans, have bilateral symmetry. This means that when the animal is cut in half down the middle, two practically identical pieces are produced. However, when cut in half across the middle, two dissimilar pieces are produced. "Bi" means symmetrical in two planes.
Other animals exhibit radial symmetry or asymmetry. Starfish are an example of an animal with radial symmetry. An animal with radial symmetry seems to radiate out from a central point. When cut in half down the middle or across the middle, two practically identical pieces are produced. Asymmetrical animals, like sponges or amoebas, have no symmetry.