Manual Payment
When ur making payments not through payables. Example- Through wire or typed cheque, then u update the paid invoice in payables (by selecting payment type as manual)
Note: you can record payment for invoices that are associated with any Payment Method type, except Electronic.
Quick payment
When you create a quick payment you can select an invoice regardless of the payments terms and due date. For example, you can create a Quick payment for an invoice that is not yet due OR when you are making payment through Oracle e-Commerce Gateway .