Radio-frequency identification (RFID) is one of the modern names that is becoming increasingly popular, as a result of many years of researches and investigations. Powerful hardware and software tools have contributed, and still do, to place the radio-frequency identification as a popular and widely used technology, from large corporations to individuals, and custom applications. Although RFID offers many advantages over other technologies, it is essential to be aware of its limitations. Therefore, it will be possible to overcome the limitations and to increase its applications. As an example, cost, safety, security, transmissions formats, and international standards are important merit figures of continuous improvement. In this book, we present important proposals that will certainly contribute to the evolution of RFID. Theoretical and practical aspects are presented and discussed by the authors, and thus we invite everyone for a pleasant reading.