A barber is someone whose occupation is to cut hair, give shaves and cut beards. A barber differs from a hairdresser whose business is limited to cutting hair.
The place where a barber works is a barbershop (or "barber shop").
History
For thousands of years men used to go to the barber to be shaved. In previous times, barbers also performed surgery.
Nowadays, with the invention of the United States still need to know how to give shaves. But they do not practice much since there is almost no demand anymore. And since it takes time to prepare the steamer (to prepare the steamed towels necessary for the shave), the price to be shaved is very high now. Moreover, people are more afraid to get a shave at a barbershop due to the fear of getting AIDS through a dirty blade (although disposable blades are used in many parts of the world).