Here is a glossary of terms to help you understand "Check 21."

Check truncation - The act of stopping a check during the settlement process and from there on processing it electronically.

Epayments - payments processed electronically.

MICR Line - Stands for magnetic ink character recognition, and is the line of numbers and symbols imprinted on the bottom of a paper check that includes the bank transit number, account number, check number and check amount.

Settlement process - There are two aspects of this. When banks refer to settlement process, they are referring to the physical process of clearing checks from bank-to-bank. When businesses refer to "the settlement process," they are talking about the matching of customer payments to a transaction (invoice or debit memo).

Straight Through Processing (STP) - The end-to-end automation of the settlement aspects of the quote-to-cash process. STP involves the ability for the delivery of goods or services by a vendor to generate an electronic invoice to the buyer. This in turn automatically matches with an existing purchase order, thereby scheduling an electronic payment and payment advice so that the actual payment can be automatically posted to the vendor's accounts receivable.

Substitute Check - A paper reproduction of the original check that is its legal equivalent under Check 21 if it meets the following five criteria: