Myopia is primarily caused by the focusing system of the eyeball focusing parallel light rays in front of the retina when our eyes are in a relaxed adjustment state. The far point of a myopic eye is at a certain point in front of the eye. The occurrence of myopia is influenced by a combination of factors including genetics and environment, and the incidence is still being explored. Based on the refractive components, myopia can be classified into refractive myopia and axial myopia. According to the degree of myopia, it can be classified into mild myopia (below 300 degrees), moderate myopia (300 to 600 degrees), and high myopia (above 600 degrees). The clinical manifestations of myopia include blurry distance vision but good near vision, often with fluctuating distance vision where squinting is needed to see clearly at a distance.