The document defines and compares different types of negotiable instruments - promissory notes, bills of exchange, and cheques. It states that a negotiable instrument is a document that allows the transfer of rights from one person to another according to the Negotiable Instruments Act of 1881. It then provides details on the key characteristics and requirements for each type of instrument, such as needing to contain an unconditional promise to pay, having ascertainable parties, and being in writing. It also highlights some of the differences between these instruments, such as cheques requiring a specified banker as the drawee and always being payable on demand.