Mass Serialization is the process that manufacturers go through to assign and mark each of their products with a Unique identifier

Unique identifier

With reference to a given set of objects, a unique identifier is any identifier which is guaranteed to be unique among all identifiers used for those objects and for a specific purpose...

 such as an Electronic Product Code

Electronic Product Code

The Electronic Product Code is designed as a universal identifier that provides a unique identity for every physical object anywhere in the world, for all time. Its structure is defined in the EPCglobal Tag Data Standard , which is an open standard freely available for download from the website...

 (EPC). The marking or "tagging" of products is usually done in the manufacturing process through the use of various combinations of human readable and/or machine readable technologies such as DataMatrix barcodes or RFID. Mass Serialization is done to enable many valuable traceability

Traceability

Traceability refers to the completeness of the information about every step in a process chain.The formal definition: Traceability is the ability to chronologically interrelate uniquely identifiable entities in a way that is verifiable....

 use cases mentioned in Track & Trace

Track & Trace

In distribution and logistics of many types of products, track and trace or tracking and tracing, concerns a process of determining the current and past locations of a unique item or property....

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