These two amphibians look very similar at first glance, but you'll notice tell-tale differences when looking closer.
Technically, all toads are frogs but not all frogs are toads. Why? They all belong to the order Anura (ancient Greek for "without a tail"), commonly referred to as "frogs". Within this order, there are different families, such as the family bufonidae - all of its members are toads. In the UK, we have two species of each frog and toads, but you'll most likely see common frogs or common toads, so we'll focus on these two.
Here's what to look out for.
Skin
This is probably the easiest way to tell the two apart. Frogs have smooth and slimy skin with a yellow to brown colour and a distinctive brown patch behind the eyes. Toads' skin is dry and somewhat warty, dry-looking skin with a brownish colour. The slimy look of frogs (they don’t feel slimy!) is caused by the secretion from glands in the skin, which keep it moist and supple. This is extremely important as frogs breathe through their skin as well as through their lungs. Toads do this to a lesser extent.