Promissory Note:
As per section 4 of the Negotiable Instrument Act. 1881, 'A promissory note is an instrument in writing( not being a bank-note of currency-note) containing an unconditional undertaking signed by the maker, to pay on demand or at a fixed or determinable future time a certain sum of money only to , or to the order of, a certain person, or to the bearer of the instrument.'