I wear glasses my vision is terrible. I am near-sighted.
That is exactly what they are used for, vision correction.
I wish I could see without them though, my vision is so bad I need my glasses to find my glasses if they fall off my night stand.
Oh my! You may need some safety glasses in case you fall providing protection for your eyes.
I used to have prescription safety glasses when I worked in the lab. I had to protect my eye from splash damage. 
you may need a strap for them as that would help them from falling off.
They don't end up falling off really. Do you know how they make glasses?
No but they consist of glass or hard plastic lenses with a frame.
Oh okay. I always wondered how they did all thoe coatings and if any of them were ever worth it. For scratches or sunlight. 
sun glasses are used for protection from the sun.