Conjunctivitis is more commonly known as "pink eye". It is an inflammation of the membrane that lines your eyelid and part of your eye. It causes blood vessels to become more noticeable, resulting in the pink or red coloring. Conjunctivitis rarely affects vision, and is very contagious so early detection is important. The cause is either a viral or bacterial infection, or an allergic reaction. In babies, it can be caused by an incompletely opened tear duct. Symptoms include redness, itchiness, a gritty feeling, a discharge that forms a cruse in one or both of your eyes, and tearing. If it is bacterial, antibiotic eyedrops or ointment may be used to help cure it. If it is viral, unfortunately there is no treatment and you have to let the virus run its course. If it is due to an allergic reaction, allergy eyedrops may be prescribed. As mentioned before, bacterial conjunctivitis is extremely contagious so good hand washing is important.