These are benign growth on surface of skin. They most commonly appear on face, neck and under arms. Usual causes are: genetic, hormonal imbalance, pregnancy & insulin resistance.
Wart is a viral disorder that hails from human papilloma virus. This makes it contagious. Talking of appearance, a wart is a hard lump in the skin which can appear reddish-brown on the outside. It is thick, hard and flat on the top but goes deeper into the skin.
These can be easily treated with radio frequency cautery which is done after giving anesthesia either via cream application or local injection. Complete removal without any scarring is possible when it is done by an experienced doctor.