Glasses play many and varied roles in lasersystems. Laser glass realizes the high powers needed for inertial confinement fusion research. Rare earth doped fiber laser and amplifier has recently received growing attention in optical fiber communication systems. Glass containing a high amount of rare earth can be used as Faraday isolators and high voltage sensors. More recently, third-order nonlinear glass has drawn significant interest as a materials for optical bistable switching. The present paper briefly reviews on the characteristics of these glasses.