The visual functions of the eye are carried out by specialized structures in the eyes. The lens can change its focal length by becoming more convex during near work (accommodation), pupil can change its size to regulate the light entering the eye in bright light (pupillary reaction to light) and retinal photoreceptors can change their sensitivity to light and its spectral (color) components during dim illumination (Purkinje effect). This chapter discusses the different signs and symptoms related to the eye problems and describes the process to correctly detect and diagnose them by thoroughly examining the different eye parts. The eye examination includes Inspection of face, orbit and the periorbital region; different visual acuity tests; external ophthalmic examination; anterior segment examination with slit lamp; and posterior segment examination. The retina, which is the most integral part of the eyes, has a refractile, orange-red appearance, with a bunch of blood vessels. Fundoscopy is a test that helps enable detection ocular as well as systemic illnesses. There are a number of chronic systemic diseases, such as hypertension, diabetes and atherosclerosis, which affect the retinal vessels.