Glaucoma is a chronic eye disease, which can be controlled but cannot be cured. If left untreated, loss of vision occurs gradually and even become blind. The detection and diagnosis of glaucoma is important. In glaucoma, Optic Cup (OC) is dependent on the type of glaucoma and the level of intra ocular pressure. Localization of Optic Disc (OD) simplifies the segmentation. OD and OC detection is a primary step in developing an automated algorithm for glaucoma detection. The paper provides overview of the different methods for optic cup and optic disc detection from retinal image.