Book excerpt: Tag Protocols; Protocol Terms and Concepts; How Tags Store Data; GS1 SGTIN Encoding; Find the header; Find the partition; Concatenate the header, filter value, and partition; Append the Company Prefix, Item Reference, and Serial Number; Calculate the CRC and append the EPC to it; Singulation and Anti-Collision Procedures; Slotted Aloha; Adaptive Binary Tree; Slotted Terminal Adaptive Collection (STAC); EPC UHF Class I Gen2; Tag memory; Inventory commands; The Select command; Access commands; Tag states; Tag Features for Security and Privacy; Destroying and Disabling Tags.