Section 18, The Companies Act, 2009

(1) An incorporated company may be either a company– (a) having the liability of its members limited by the memorandum to the amount, if any, unpaid on the shares respectively held by them (in this Act termed “a company limited by shares”); (b) having the liability of its members limited by the memorandum to such amount as the members may respectively thereby undertake to contribute to the assets of the company in the event of its being wound up (in this Act termed “a company limited by guarantee”); (c) not having any limit on the liability of its members (in this Act termed “an unlimited company”). (2) Any of the companies mentioned in subsection (1) may either be a public or private company.