1. When meeting strangers: When cats are young, they spend a long time in contact with female cats, so there are few strangers, so when they meet strangers, they will explode out of fear of the unknown.

2. When the cat meets a dangerous opponent: When the cat meets an animal bigger and stranger than itself outside, it will scare these animals away by blowing hair. And the cat's body bends while exploding, ready to attack animals at any time.

Cats, belonging to cats, are widely used as pets in families all over the world, with parasites such as tinea, fleas and Toxoplasma gondii. The ancestors of domestic cats are supposed to be desert cats in ancient Egypt and Persian cats in Persia, which have been domesticated by humans for 3500 years (but not completely domesticated like dogs).