Cats enjoy physical contact because they're fairly social animals. In the wild, feral cats live in loose colonies. They display behaviours like mutual grooming and co-sleeping. Petting your cat is a stand-in for the mutual grooming they would have engaged in with other cats.
What do cats feel when you pet them?
Purring. The most obvious and common way cats show their happiness and love is through purring. Cats seem to have a special little motor inside them that get started when they are relaxed and enjoying something. You'll often hear this rumbling, vibrating noise while you are petting your cat.
Why do cats like being patted on the back?
You're giving kitty some love, scratching behind his ears and stroking his back. He raises his hear higher and higher in the air. Happily, he sticks his tail straight up and maneuvers his butt right in your face. Kitty isn't trying to tell you off; it's a sign of affection.