Contact lenses sit directly on your eyes and cause less distortion. Whereas, glasses leave a space between the lenses and your eyes. This distance can distort the size of objects, making them look larger or smaller than they actually are.
Since contact lenses sit directly on your eyes, this ensures that your entire field of vision is in focus. If you look up, down or to the side with your glasses on, your vision will not be as sharp for the reason that glasses only improve eyesight in the field of vision directly in front of you.
Outside factors normally don't affect contacts, while your glasses can smudge when you touch them, fog up with temperature changes, and get blurry when wet.
Glasses can be uncomfortable, heavy, and slip down the bridge of your nose. The lenses can then get knocked off your face, leading them to become scratched or broken. On the other hand, contact lenses sit securely on your eyes and if fit properly , will not move around.
Contacts allow others to see your eyes naturally, without altering their appearance. For many, this can increase confidence and self-assurance.
However, when considering lenses, remember that contacts are medical devices, and should be viewed as a serious responsibility. Contacts aren't right for everyone so talk to your doctor at your next visit.