What is a "sty"?

What is a "sty"?

Robert K. Maloney (Ophthalmologist) gives expert video advice on: Are my frequent headaches due to vision problems?; What can cause temporary blindness?; What should I do if I lose my vision suddenly? and more...

A sty is a plugged up tear gland in the edge of your eyelid. It's basically a pimple of your eye. And just as sweat glands get plugged up on your face, if a tear gland gets plugged up, it gets swollen, infected, red, irritate, hot, painful.