Dogs express their affection and closeness to their owners through licking. This is a natural social behavior, a way for them to show their affection for their owners. Licking helps establish and maintain a close bond with the owner.

Dogs are born with keen senses of smell and taste, and they explore the taste of their surroundings through licking. Licking their owners may be because they are curious about their owner's scent and want to get to know them better.