A limited partnership is different from a general partnership in that it requires a partnership agreement. Some information about the business and the partners must be filed with the appropriate state agency (usually the secretary of state).
Additionally, a limited partnership has both limited and general partners. A limited partner is one who does not have total responsibility for the debts of the partnership. The most a limited partner can lose is his investment in the business. The trade off for this limited liability is a lack of management control: A limited partner does not have the authority to run the business. He is really more or less an investor in the business.