A loan agreement, or a promissory note, can take many different forms. Secured notes are those that require something to be put up as collateral, and unsecured don't. The interest rates can remain the same through fixed rates, or be variable as a changing rate. While monthly payments can be agreed upon, any outstanding amounts owing can be required to be paid on demand or on a specific date. Finance agreements can take many forms, and go beyond simple loan agreements. The following list of templates and sample contracts that can be used.