A hole in the heart is a nonmedical term for a type of congenital heart defect. There are many types of holes in the heart, and most are present from birth. Around 1% of babies born in the United ...

A macular hole is when an opening forms in the middle of the light-sensitive tissue at the back of the eye. It can lead to people having a blurry or black spot in the center of their vision. The ...

Albert Einstein's theory of gravity, general relativity, may not be the best recipe to describe black holes. When you purchase through links on our site, we may earn an affiliate commission. Here’s ...