A kitten is a juvenile cat. After being born, kittens display primary altriciality and are totally dependent on their mother for survival. They do not normally open their eyes until after seven to ten days.

After about two weeks, kittens quickly develop and begin to explore the world outside the nest. After a further three to four weeks, they begin to eat solid food and grow adult teeth. Domestic kittens are highly social animals and usually enjoy human companionship.

Domestic kittens in developed societies are usually vaccinated against common illnesses from two to three months of age. The usual combination vaccination protects against feline viral rhinotracheitis (FVR), feline calicivirus (C), and feline panleukopenia (P).

This FVRCP inoculation is usually given at eight, twelve, and sixteen weeks, and an inoculation against rabies may be given at sixteen weeks. Kittens are usually spayed or neutered at seven months of age, but kittens may be neutered as young as seven weeks (if large enough), especially in animal shelters. Such early neutering does not appear to have any long-term health risks to cats, and may even be beneficial in male cats. Kittens are commonly wormed against roundworms from about four weeks.