DEX or DEX/UCS stands for Data Exchange/Uniform Communications Standard. Within the vending industry, It defines the transfer of information/data between a Hand Held Computer (HHC) or Data Collector and the electronic vending machine. The Food Marketing Institute, along with the major food retailers, defined the original DEX framework in the mid 70s. Their objective was to standardize the transfer of product information between a supermarket's computer and the delivery driver's HHC. Coca-Cola, recognized the benefit of faster back door check ins using the DEX concept and quickly merged it into their HHC software. As Coca-Cola moved more into electronic vending, they also realized that if their vending machines had DEX capabilities their CASH reconciliation could be both simplified and much more efficient. In the early 80's Coca-Cola began specifying basic cash DEX data capabilities in new vending equipment.

About 1986, NAMA's Vending Technology Standards Committee created the DEX Data Transfer Standard (DTS). This set the baseline for information to be collected in a vending machine and how that information would be retrieved. At that time, the DEX protocol was incorporated as an integral part of the DTS. Thus, a DEX standard was established, but continues to evolve, with both vending machine and product manufacturers employing variations that fit their individual objectives, just as the mass-food retailers still do for their purposes.

In the early 90's, recognizing the need for plug-n-play DEX upgrade technology and uniform DEX data access, InOne, which was ASC at the time, began mapping the vending DEX universe. Today the top 4 vending software providers rely on InOne's DEX decoding library and field technician training to facilitate their DEX processing technologies. In 2000, InOne wrote the guidelines for the newly adopted Edition 6 of the international DEX/DTS standard, at the invitation of NAMA and the European Vending Association (EVA).