Breaking Down Myopia: Understanding the Real Causes of Blurry Vision

Myopia is a refractive error, meaning it's related to how the eye focuses light. In the case of myopia, the eye's longitudinal length is too long relative to the focusing power of the cornea and lens, or the cornea and/or lens is too curved for the length of the eyeball. As a result, when a person tries to look at distant objects, the image that forms is in front of the retina, making the distant object appear blurry.
The most obvious symptom of myopia is blurry vision when looking at distant objects. Other symptoms may include:

Squinting
Eye strain
Headaches from eye strain
Needing to sit closer to the television, screen, or front of the classroom