A werewolf is a human that transitions into wolf form during a full moon and has no control of the transition.
In the wolf form, they usually much bigger than an actual wolf and is able to walk on its hind legs so this is a big indicator whether or not it is a wolf, or a werewolf.
There are a lot of folklore and stories about werewolves, each and everyone differs slightly.
Common weaknesses of a werewolves are silver knives and bullets and wolsbane (a plant).
To become a werewolf, there are ways such as being bitten by another werewolf, and others such as being contaminated by bodily fluids such as saliva, blood and urine.
Werewolves feed on meat because they are carnivore. They have no blood lust and boys are usually born into it while females usually have to mate with a male who has werewolf genes.