I'm sure at some point you've felt the nagging discomfort of having a stye on your eyelid. Styes are similar to a pimple, but they form on your upper or lower eyelid. The stye inflammation of the eyelid can be caused by a couple things—either an oil duct is blocked up on your eyelid, or germs such as a staphylococcal bacterium have been trapped with dead skin cells on the eyelid. Usually, styes are never more than a superficial frustration, but they can form deeper in the eyelid.