Standardization (also known as normalization) is the process of converting an input address into a format that adheres to USPS standards. These standards define a ruleset for how each component of an address should be formatted. Some of these standards are stylistic preferences (e.g. ALL UPPERCASE is preferred) while others are more prescriptive rules.
Geocoding is the process of converting an address into a coordinate (coordinates are commonly referred to as “geocodes”). Many geocoding systems can also go a step further and determine the coordinates of place names like “The Grand Canyon” where a set address may not exist. There are typically a few different levels of geocoding depending on your desired degree of precision...
A ZIP (Zone Improvement Plan) Code is a code assigned to specific geographic regions in the United States - this code is used by the United States Postal Service (USPS) to sort and deliver mail more effectively.
ZIP Codes are tied to addresses and, like addresses, are distinct. This means that where one ZIP Code ends another begins without any transition area. Also, there are some large areas in the US without any addresses and so those regions are not applied to any ZIP Code. These areas without ZIP Codes are mostly located in Alaska and desert regions in the Southwest region of the US.
Most people are familiar with the basic 5 digit ZIP Code - you use this when you enter your address into a website to order a pizza or get a delivery from Amazon. These 5 digit ZIP Codes are usually applied to one specific post office. This makes the sorting process much easier for USPS employees; they don’t need to spend time looking for which Post Office in Atlanta delivers to a particular street because they have a ZIP Code to tell them. Using a ZIP Code is not strictly required to deliver a piece of mail, but it will substantially speed up the delivery.
FIPS codes are unique 5-digit geographic place codes applied to states, counties, and certain areas of possession within the United States. The acronym, “FIPS”, stands for Federal Information Processing System and was established in the early 1970’s by the Government agency, NIST. NIST, which stands for “National Institute for Standards and Technology”, created FIPS codes to establish government mandated industry standards. These codes were used between government agencies and other technical organizations to ensure consistency and uniform practice. These codes have evolved over the years from a digit structure standpoint and the current FIPS codes being utilized are the FIPS 5-2 (state codes) and the FIPS 6-4 (county codes). These codes were dropped in 2008 by the NIST and replaced with INCITS 38-2009 for the 5-2 code, and INCITS 31-2009 for the 6-4 code. The FIPs codes are still used by numerous federal organizations across the United States.
An RDI or Residential Delivery Indicator tells you whether an address is a business or a residential location. The database of USPS monitors addresses registered particularly for commercial purposes. Authorized software and programs have access to this data.
CASS (Coding Accuracy Support System) Processing is the method of testing the accuracy of address matching and correction software. The USPS offers CASS Certification to any software developer, mailer (UPS or FedEx, for example), or Service Bureau looking to improve the accuracy of their address matching software.
Most of the time when you put a letter in the mail the only notification you will receive is from the recipient saying “Hey, I got your letter!” But what if you have something important or valuable to send, and you want to make sure that it arrives safely? If it’s valuable, you might want the mailman to actually deliver it to the person instead of just leaving it in the mailbox or mailroom. That’s where you want Certified Mail - an upgraded delivery service offered by USPS.