Cats have a habit of rubbing around your legs when you return home, even if you have been gone only for a short time. They will jump up and head-butt you in the face when you're sitting down or trying to sleep, and they rub their faces on door frames, the fridge, cupboard doors, the sofa and many other locations around the house. It is part of the way that cats communicate as they spread their scent around.
The Importance of Scent
Cats have a sense of smell that is about 200 times more sensitive than a human. They also have an organ in the roof of their mouth that senses pheromones. Cats have many scent glands including on the tail, paws, forehead, cheeks, chin and lips. When your cat rubs these scent glands against a surface, they release pheromones that are unique to each cat and let other cats know they have been there and left their calling card.
Affection and Ownership
The pheromones secreted by face glands have a calming effect on cats and are associated with being affectionate and friendly. Cats tend to mark people and other cats by head butting, known as "bunting," and by rubbing their cheeks using the scent glands on the forehead and cheeks. They will often use the scent glands on the lips and chin to mark furniture and other objects. When we pat and stroke them when they nuzzle us, we are exchanging scents. Scent marking is how a cat lets us know they own us.
Communication With People
As well as indicating ownership and territory, the face rubbing also is used to communicate urgency such as letting you know it's their feeding time. They may rub both you and the place where the food is kept to make it clear that they are ready to be fed. Some cats also face rub when the litter box needs cleaning. If they head butt and then offer their neck sideways with their head tucked down, they are seeking attention in the form of stroking or scratching.
Interaction With Other Cats
In a multicat household, cats will rub faces to exchange scents with each other. This allows them to be more comfortable with each other and generates a sense of security in a territory that has a group scent. Cats will often rub their face on an object where another cat has left his scent. The pheromones left give information about the cat to others and is used by cats to advertise mating availability.