Purpose: To present an overview of the recent observations and research that shed light on the understanding of open and closed angle glaucoma. Methods: Literature review. Results: Glaucoma is a major eye problem afflicting millions of people worldwide. As the population increases, the number of people with glaucoma also increases, with glaucoma becoming an increasing public health concern. This paper presents the natural history of open angle and angle closure glaucoma. We examine the glaucomatous progression in terms of changes in optic disk morphology and visual fi elds as well as the risk factors for progression. Conclusions: This present review highlights the magnitude of glaucoma globally and the need for a greater understanding of this disease and its natural progression.