Any human with Uratha heritage may undergo the First Change at some time in their life, becoming a werewolf, though what triggers the change is unknown. Each character has an auspice or role, and most join a tribe. Unlike traditional werewolves, Uratha may change at any time into various forms between man and wolf, though they do find this easier when the phase of the moon matches their auspice.
Uratha are fierce territorial predators who feel the compulsion to hunt. Many have trouble containing their aggression, hindering their ability to live normal human lives. Like wolves, the Uratha form packs in order to hunt more efficiently and better guard their territory.
Uratha are also spiritual creatures, able to channel spirit energy, which they call Essence, to make use of supernatural powers called gifts to aid them in their hunts. They also possess an instinctive (if rudimentary) understanding of the First Tongue, the language spoken by their ancestors and spirits (possibly also the original language of all humans). Many Uratha learn to speak the First Tongue fluently.
*via the White Wolf wiki*