Cats claim and defend certain areas. What is this called?

The behavior of cats claiming and defending certain areas is known as territoriality. Cats establish territories to ensure access to resources such as food, shelter, and mates while also reducing competition from other cats. This instinctual behavior can manifest in various ways, including marking with scent, vocalizations, and physical displays to ward off intruders. Territoriality is an important aspect of a cat's social and survival strategies.