CASS is an acronym. It stands for Coding Accuracy Support System, a system and methodology created by the United States Postal Service (USPS) in order to improve the deliverability of mail. By using specially licensed CASS software, organizations can improve the deliverability of their mail pieces.
Most large volume commercial mailers use a form of address cleansing service in order to improve delivery and reduce costs by not sending mail to undeliverable addresses.
NCOA is an acronym that stands for National Change Of Address. This acronym describes the change of address service offered by the USPS. Whenever someone moves and files a change of address card with the USPS, their address gets entered in the NCOA database.
DPV is an acronym that stands for Delivery Point Validation. This is the term used to describe whether a given house or building number actually exists on a given street. Without DPV, CASS software could generate a Zip +4 barcode without actually determining whether a piece of mail was deliverable. All good CASS software now includes a DPV feature.
This is just another way to describe a zip code that has 4 additional digits associated with it to further describe a mailing address. All good CASS software should return both the Zip+4 digits as well as the digits required to allow printing of the Zip+4 barcode (Postnet Barcode).
This refers to the small vertical bars on nearly every piece of mail that goes through the USPS. The barcode doesn't look like a barcode that you would see on product in the store that used at the checkout counter, instead these are short evenly spaced bars of two different heights. USPS sorting equipment sorts mail by reading these bars. In addition, the USPS sprays bars on the bottom of any mail piece that doesn't already have them. You can typically find them above or below the mailing address on a piece of mail or on the bottom edge of a mail piece.