Cats are fascinating creatures, constantly keeping their humans guessing. Once you think you crack the code with one, he goes and does something else that has you scratching your head. The body language of bumping heads with other cats is definitely baffling, although it often is just a classic and straightforward expression of tenderness and love.
When cats bump heads with each other, it's often their feline way of establishing a connection. Cats' faces are equipped with scent glands that give off their individual pheromones. If cats bump their heads together, they offer each other their own specific scents, and therefore "label" each other as being soothing, friendly and familiar presences. This behavior is often referred to as both "bunting" and "head-butting." If a pair of cats bumps heads together, you can bet they're probably pretty fond of each other. The scents cats rub onto others are essentially impossible for people to pick up on, but are also extremely distinctive and recognizable to them. When it comes to olfactory skills, cats are far superior to people.
Although bunting in cats is often a simple caring and loving gesture, it also can be as casual as a polite acknowledgement of jovial recognition. If a cat comes across another feline that he has friendly feelings for, he might softly bump his head against the other cat's. Some cats also say "hi" to each other by rubbing their noses together, as well.
Bumping Heads With People
Head-butting behavior doesn't exist only between cats. Cats often bump their heads with the closest humans in their lives, and sometimes even with canine buddies, too. The intentions behind the action are often similar -- bonding and being friendly. Cats also frequently massage their heads against peoples' heads to label them as being property, but the behavior is still a sincere compliment. The cats admire the "head-buttees" enough to want to "own" them, after all.
Head bumping as an action signifies a cat's feelings toward another human or animal, and at the same time, it also signifies their current mood in a general sense. If a cat is feeling at ease, serene and like everything is good in the world, he might just show it by head-butting the individuals around her. Cats who are tense, scared or nervous in any way tend to forgo that kind of laid-back body language.