The PADIS codeset is a set of industry standardised codes that can be used to describe an element in a way that can be interpreted in a way not specific to a single company. For example, if a flight has an active check-in status, you may want to return PADIS code 198 from codeset 9321, which indicates this. A tech partner can interpret this PADIS code and understand what it means without needing to rely on a text based response from the airline.