Common warts can be found on the hands, feet, forearms, and face and range in size from a pinhead to a small bean.  They can also occur on the voice box or the larynx and cause hoarseness.  They are rough, irregular skin growths that are caused by a virus.  They may be flat or raised, dry or moist, and have a rough and pitted surface that is either flesh-colored or darker than the surrounding skin.  Highly contagious, they can be spread by picking, trimming, biting, or touching them.  They can also spread onto the face by shaving.  Common warts most often occur on skin that is continuously exposed to friction, trauma, or abrasion.  They typically do not cause pain or itching and can be left to disappear on their own unless they become bothersome....