Class: Mammalia
Order: Carnivora
Family: Felidae
Genus: Felis

In a general sense of the word cat can mean any mammal of the felids or felines. It may include large cats such as lions or tigers (occasionally referred to as Big Cats). 


Sheba cat. image: Dovenetel/wikipedia

Wikipedia notes that

However, commonly the term cat means  the domestic cat,  (Felis catus  or Felis silvestris catus ) is a small, usually furry,domesticated, carnivorous mammal.

It is often called the housecat when kept as an indoor pet, or simply a cat when there is no need to distinguish it from other felids and felines.

Cats are valued by humans for companionship and their ability to hunt vermin and household pests. Historically this has led to cultural significance of cats in literature and even religion.

Compared with dogs, cats tend to have a finer less robust structure that is more flexible.  Cats have free floating clavicle bones (3 in diagram below) that allow them to squeeze their bodies through spaces the same size as their heads.

Anatomy and skeleton of cat.  A – Cervical or Neck Bones (7 in number). B – Dorsal or Thoracic Bones (13 in number, each bearing a rib). C – Lumbar Bones (7 in number). D – Sacral Bones (3 in number). E – Caudal or Tail Bones (19 to 21 in number).  1 – Cranium, or Skull. 2 – Mandible, or Lower jaw. 3 – Scapula, or Shoulder-blade (free floating). 4 – Sternum, or Breast-bone. 5 – Humerus. 6 – Radius. 7 – Phalanges of the Toes. 8 – Metacarpal Bones. 9 – Carpal or Wrist-bones. 10 – Ulna. 11 – Ribs. 12 – Patella, or Knee-cap. 13 – Tibia. 14 – Metatarsal Bones. 15 – Tarsal Bones. 16 – Fibula. 17 – Femur, or Thigh-bone. 18 – Pelvis, or Hip-bone. image credit: Przemek Maksim

Another distinguishing feature of cats is that they have retractable claws which allows them to climb objects such as trees fairly easily.  The eye socket of domestic cats is also relatively large that allows them to hunt in dim light.

Adapted from 

Cat. (2015, January 20). In Wikipedia, The Free Encyclopedia. Retrieved 03:00, January 21, 2015, from