The tail of a cat is an extension of its spine
The cat's tail is an extension of the spine and is used to help him balance and as an aid to communication. The tail is an important tool to help keep kitty balanced when he walks along a fence. The tail is used as a counterweight, if he looks left, the tail will move in the opposite direction. Approximately 10% of the bones in the cat's body are found in the tail. These bones are known as "caudal vertebrae". There's no set number of bones in the cat's tail, but an average number is between 20 and 23. This depends on the breed of cat and the length of the tail.