Optical computing is the science of making computing work better using optics and related technologies. Optical computing is dead only if we foolishly define it as the attempt to supplant electronics. Optical computing generally means that the optical manipulation of discrete manipulating data. The hope for optics lies in doing things that are provably impossible for electronics. This paper consists of different types of optical computing environments (mainly digital, analog and quantum), how the network has been transported in optics (since 1990, SDH and SONET specifications have been extended based on demand for the transport of new tributary signals and also based on new capabilities provided by the evolution in component technology), architecture of optical computing, role of non-linear materials in optical computing. How optical computing has been used in today’s computing world and what is the future scope of optical computing, what are the devices used for optical computing.