A common belief says that cats always land on their feet; well they usually
do - but not always. A cat can reflexively twist its body and right itself using
its acute sense of balance and flexibility. This is known as a cat
'righting reflex'. It always rights itself the same way, provided it
has the time to do so during a fall. Certain Cats that don't have a tail are a
notable exception, since a cat moves its tail and relies on conservation of
angular momentum to set up for landing.
Video - Cat Legs
Like dogs, cats are digitigrades, meaning
they walk directly on their toes, the bones of their feet making up the lower
part of the visible leg. Cats are capable of walking very precisely, because
like all felines they directly register, that is, they place each hind paw
(almost) directly in the print of the corresponding forepaw, minimizing noise
and visible tracks. This also provides the cat sure footing for their hind paws
when they navigate rough terrain.
As with many predators, cats have retractable claws. This is actually a misnomer
because in their normal, relaxed position the claws are sheathed with the skin
and fur around the toe pads. This is done to keep the claws sharp by preventing
wear from contact with the ground. It is only by stretching, such as a cat
swatting at prey, that the connecting tendons are pulled taut, forcing the claws
to extend. Thus, extending the claws is an involuntary action for cats.