This iconic picture shows the most basic test of eye vision, which is a basic component of any eye test. One eye is covered with a patient and the letters on the well lit Snellen chart are read out by the patient and displayed in the decreasing size form. It is a baseline assessment of clarity of vision by measuring the eye capacity to identify shapes and details at a specified distance in a simple and essential test. Although today the exams have more sophisticated technological aspects in which there is deeper analysis of the health, the eye chart is a universally accepted image of mind about the eyes. It is the initial beginning in detecting refractive errors such as short sightedness or long sightedness and specifying the required prescription to include corrective glasses and have clear and comfortable foresight.