Tinnitus is any kind of noise that a person may hear in their ears or head that is not coming from an outside source. These noises can be ringing, buzzing, hissing, humming, high and low pitch tones, etc.
Sometimes, the cause may be as simple as having wax in your ears. At other times, it may be a symptom of hearing loss or medications that you may have taken. Tinnitus can also be caused by overexposure to noise.