This document provides a comprehensive overview of ocular microbiology, focusing on the microbial agents responsible for ocular infections, their diagnosis, and implications for public health. It details the anatomy of the eye, the normal conjunctival flora, and the influence of factors such as age, climate, and contact lens use. The document emphasizes the role of commensals, opportunistic pathogens, and the eye's immune defenses. It outlines the etiology, clinical features, and treatment considerations for bacterial and viral conjunctivitis, highlighting common pathogens like Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and adenoviruses. Follicular conjunctivitis and conjunctival infections from viruses like HSV and VZV are also examined. Additionally, it explores ocular parasitic diseases including toxoplasmosis, cysticercosis, echinococcosis, and toxocariasis, describing their life cycles, transmission, and diagnostic approaches. The text underscores the evolving landscape of ocular infections due to immunosuppression, contact lens use, and global health trends, stressing the importance of molecular diagnostics and preventive strategies.