What does this duo even mean?

Puppies begin social play with play-biting, pawing, and barking. The intensity escalates and becomes more complex as the dog matures. The first play-eliciting gesture seen in puppies is the raised paw. The play bow, is the classic invitation for a canine romp and is used by older pups and adults, along with barking, leaping forward to nose-poke and then withdrawing, face pawing and licking.