I recall that "spectacles" would be the preferred word when I was growing up. It was often shortened to "specs".
"Glasses" were the ones you wore either in the sun (sunglasses) or while driving or to protect your eyes from wind or dust. "Glasses" were never the ones you wore because of a weak eyesight.
However, nowadays, I see people using "glasses" for all sorts of eyewear whether it's for eyesight (what we used to call "spectacles") or for the sun or wind/dust. I am curious how this change happened. Is it because "spectacles" is UK English and the popularisation of US English led to more usage of "glasses"? Or is it something else. Thanks!