COMMON STOCK is an equity security which represents partial ownership in a  corporation. The holder is entitled to share in the profits of the company, to vote, and to share in the liquidation value of the assets. 

PREFERRED STOCK represents ownership in the issuing corporation and has prior claim on dividends. In the case of bankruptcy, preferred stockholders have a claim on assets ahead of common stock holders. 

CONVERTIBLE STOCK may be exchanged for common stock at the owner's option according to a specified formula set at the issuance date.