Lasers is a brief, engaging glimpse at the microscopic and macroscopic world of the laser. More than three decades ago, lasers put the power of the photon in our grasp. But the Age of Optics has only just begun. Harbison and Nahory, who are experts in lasers and laser-related semiconductors, describe how excited electrons inside lasers release photons, which are directed by mirrors into a single, potent beam of light. These beams can repair a damaged eye, play a compact disc or carry a telephone conversation across the ocean. Using lavish illustrations and well chosen examples, the authors explain how lasers so tiny that they are invisible to the naked eye, and made of materials built atom by atom, are possible.