While male cats are often friendlier and more affectionate than females, cats' personalities depend largely on early socialization and whether they are spayed or neutered. Intact female cats focus more on kittens and litters than on humans, while intact males can be aggressive and dominant.
To the disdain of pet owners, an intact male cat is prone to spraying, which is the release of a pungent and powerful scent along with his urine. He is also more likely to challenge his owners for dominance. An intact female cat goes into heat starting at the age of 6 months, and her heat cycle is characterized by yowling and attempting to escape to find a mate. Unless she is fixed, she can have up to three litters per year and continues to do so until she is 8 or 9 years old.
People perceive male cats as being more docile and affectionate, while female cats are generally more independent and dominant. However, once they are fixed, the differences between male and female cats are subtle and the similarities numerous. Both sexes prefer to stay closer to home and are less aggressive. Without mating or litters occupying their minds, some cats are more interested in interacting with humans. Indoor cats are usually friendlier than outdoor cats because of the increased opportunities for socialization associated with living indoors.