The process that gives rise to the beak. This process pertains to the initial formation of a structure from unspecified parts. The avian beak is an external anatomical structure, in the head region, that is adapted for feeding self and young, catching prey, probing, etc. It encompasses, but is not restricted to, the maxilla, mandible, maxillary rhamphotheca, mandibular rhamphotheca, nostril, nasal fossa, nasal bones, egg tooth and rictus.