Nearsightedness, also known as myopia, is a vision condition where objects in the distance appear blurry. It is caused by the shape of the eyeball being elongated, which causes light rays to focus in front of the retina instead of directly on it. Symptoms include indistinct vision of distant objects. Nearsightedness is often hereditary and can be treated through orthokeratology, which uses contact lenses to gradually reshape the cornea and correct vision. It affects nearly 30% of the US population and typically develops during childhood.