Frequently Asked Questions

How does a computer act on information about a product?


The whole point of automatic identification is to take people out of the loop, to enable computers to gather information and act on it. For that to happen, computers must be able to not just identify a product, but also interpret some basic information about it. To make this possible, the Auto-ID Center started to develop a new computer language called the Physical Markup Language. PML is based on the widely accepted eXtensible Markup Language (XML), which is used to describe common types of data (addresses, dates, invoice numbers and so on) and transactions (purchases, requests for quotes and so on) in a way computers running different proprietary applications can understand. PML files will be stored in the EPC Information Service (once called PML servers). EPC Information Service will reside on computers distributed across the Internet. (The Object Name Service, described above, points computers to data about products stored in the EPC Information Service.) Some information about each product will be stored in a PML file, such as a product’s name and broad category (soft drink, auto part, clothing and so on), when it was made and where, its expiration date, its current location, even its current temperature, if that’s important. PML files will provide information to existing enterprise applications or new yet-to-be developed applications. The PML file could contain instructions for where a pallet should be shipped. It could contain instructions for a point-of-sale display to lower the price of an item when its expiration date approaches. Or it could contain instructions for how long your microwave needs to cook a particular brand of frozen pizza.


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