Elephants have a thick layer of skin on the back of their feet so that they dont leave footprints and feel vibrations such as those of an approaching storm or rain.
Seals and aquatic mammals feet are shaped like paddles to help them swim by moving water more efficiently.
Birds have different types of feet. Water birds such as ducks and geese have feet joined by skin to help them swim. Hummingbird's feet for ex. are very small and not powerful because it spends very little time resting. Eagle's feet are strong and powerful to be used in hunting. Feet of penguins have sharp claws which help them to hold onto the ice
Many animals such as dogs or wolves have retractable claws. Cheetahs are one of the only cats which claws are nearly always visible because when they chase prey they can reach the speed of 103 km per hour and their claws dig in the ground to help them stabilize.
Horses, mules and donkey's all have solid hooves. The solid hoof is built for speed when crossing wide open places. Not all hooves are solid, for ex. sheeps and goats have seperated hooves which help them to walk and keep balance along mountains.
Insects feet always have small hooks on them so that they have a good grip on the surface they walk on.