A stye is a red, hot, and tender bump on the outer (and sometimes inner) edge of your eyelid. It looks like a pimple or a boil. Also spelled "sty," this bump happens when old oil, dead skin cells ...

A stye forms along the edge of your upper or lower eyelid and usually starts as a red bump. It swells larger and become hard ... A small incision is made to the inside of the eyelid to drain the oil ...