This document discusses bills of exchange under Indian negotiable instruments law. It defines a bill of exchange as a written instrument containing an unconditional order to pay a certain sum of money. It notes that bills of exchange must be in writing, name the relevant parties of drawer, drawee, and payee, outline the amount due and time for payment, and be signed. The document also describes the key parts of a bill of exchange including the amount, date, period, signature, and stamp, and identifies the two main types as bills payable at sight and bills payable after a certain period.