A stye, also known as aÂ hordeolum, is a lump on the eyelid that looks similar to a pimple, according to theÂ Mayo Clinic. Styes most commonly form on the exterior of the eyelid, but they can also form on the inside of the eyelid. The stye is usually painful and filled with pus.
Most styes don't require much treatment; however, applying a warm washcloth to the affected eye might provide some relief. A stye that doesn't improve within 48 hours usually requires medical care. Additionally, if the area around the affected eye begins to swell, medical treatment is necessary.
A stye can be contagious, but contact with an infected person isn't always necessary, notes All About Vision. Most people have the stye-causing bacterium in their body.