Every cat owner will know that cats rubs their heads against objects in their environment, such as the sofa, a cupboard, or a table leg. This behaviour has a purpose: the cat is spreading its pheromones, which it uses to mark its territory as safe and secure. For example, when a cat is ill or stressed, it may stop spreading these pheromones. As a result, the cat will no longer feel safe and secure, which can lead to unwanted behaviour.