Kids and Youth: Goggles that are small sized frames which normally fits kids 12 years old and younger.
Medium frames: Medium framed goggles fit teens and ladies best. Men can wear a medium frame but normally has a smaller field of vision.
Large frames: Fits men best. Some women can wear a large frame because they like a large field of vision but a large frame looks BIG on the face.
Interchangeable lens: These goggles include 2 lens, one for sunny days, and one for overcast days that can easily be switched within 10 seconds.
Photochromic lens: The lens on these goggles adjust the tint automaticaly depending on the light.
Over The Glasses goggles are designed for people who need to wear glasses on the slopes.
Some goggles fall into 2 frame size categories. Example: a medium/large frame would be in both a medium and large category.
More about goggle sizing: Normally a small frame goggle fits kids and youth, medium frames fit teens and ladies while large frames fit men. Some people prefer a smaller frame goggle because it looks better on their face but keep in mind a larger frame goggle offers a better field of vision which is important as you go down the slopes.