A due bill is an acknowledgment and evidence of a debt. It may be payable in money or in merchandise. The ordinary form of due bill is not negotiable.

How Notes Differ from Other Contracts. There are three peculiarities which distinguish promissory notes from ordinary written contracts.

1. Notes are negotiable.

2. There is no statement in a note of consideration.

3. There are no days of grace allowed on ordinary contracts.

A note must have a clear promise to pay, without any attached conditions. The time must be certain, that is, it must not depend upon the happening of some uncertain event.