I have amazing eyesight! Some people will call it a good visual acuity! 
Lucky! I have horrible eyesight. I have to wear glasses. Does visual acuity mean 20/20 or better?
It just refers to how good or bad the eyesight is. Some people have refractive errors or abnormalities in the shape of their eyeballs.
I'm guessing refractive errors make it harder for them to see? How good is your vision?
yeah, definitely makes it hard to see. It changes the way the light is focused onto the retina. My eyes are pretty aawesome!
You are so lucky. I am nearsighted, so whenever I take my glasses off, I'm practically blind.
Ah too bad. At least it can be corrected by optical means, like glasses. Or if you're interested, laser surgery.
Laser surgery freaks me out! I would love to do it, but the thought of it scares me. What do you think about contact lenses?
Contact lens
A contact lens, or simply contact, is a thin lens placed directly on the surface of the eye. Contact lenses are ocular prosthetic devices used by over 150 million people worldwide, and they can be worn to correct vision, for cosmetic, or therapeutic reasons. In 2004, it was estimated that 125 million people worldwide use contact lenses, including 28 to 38 million in the United States. In 2010, the worldwide market for contact lenses was estimated at $6.1 billion, while the US soft lens
Visual perception
Visual perception is the ability to interpret the surrounding environment using light in the visible spectrum reflected by the objects in the environment. This is different from visual acuity, which refers to how clearly a person sees (for example "20/20 vision"). A person can have problems with visual perceptual processing even if he/she has 20/20 vision.
The resulting perception is also known as visual perception, eyesight, sight, or vision (adjectival form: "visual", "optical", or "