Abstract —This paper describes different aspects of a typical RFID implementation. Section 1 provides a brief overview of the concept of Automatic Identification and compares the use of different technologies while Section 2 describes the basic components of a typical RFID system. Section 3 and Section 4 deal with the detailed specifications of RFID transponders and RFID interrogators respectively. Section 5 highlights different RFID standards and protocols and Section 6 enumerates the wide variety of applications where RFID systems are known to have made a positive improvement. Section 7 deals with privacy issues concerning the use of RFIDs and Section 8 describes common RFID system vulnerabilities. Section 9 covers a variety of RFID security issues, followed by a detailed listing of countermeasures and precautions in Section 10. Keywords —RFID, RFID Standards, RFID Protocols, RFID Security, EPC structure, RFID Applications, RFID Classification 1. I NTRODUCTION A wide range of Automatic Identification (Auto-ID) systems including magnetic stripes, Opt-ical Character Recognition (OCR), barcodes, biometrics, contact memory buttons, and smart cards have been around for many years and have helped in increasing the efficiency as well as efficacy of different business processes. Each of these technologies has their pros and cons and has specific target-applications for which they have their niche markets. Although OCR systems allow simultaneous manual and auto-identification, the prohibitive cost of the readers prevented the widespread use of the technology in applications other than banking and production [1]. While barcodes have proved to be a cost-effective way for managing inventory, they have cer-tain inherent disadvantages such as limited information-storing capacity; a strict line of sight requirement between the scanner and the barcode, which effectively prevents multiple barcodes to be processed simultaneously; limited data redundancy and error correction; and a lack of in-built data-security standards in various symbologies. Biometrics, such as fingerprinting, retina scans, iris scans, and voice recognition are all considered to be strong identification solutions in automatic access control but some people find these technologies obtrusive thereby limiting their exposure. Contact memory buttons are robust Auto-IDs that are capable of withstanding adverse environments that overcome a number of barcode system limitations and support fea-tures such as high data storage capacity (up to 8 MB), the ability to write data multiple times, and data security using encryption. However, despite these advantages, the requirement for con-