RFID, in English radio-frequency identification, stands for identification with the help of electromagnetic waves. It refers to a technology for transmitter-receiver systems for automatic and contactless identification and localization of objects and living beings with radio waves.
The system consists of a transponder and a reader for reading the identification. They can be as small as a few millimeters and implanted in pets, for example.
Coupling takes place by means of alternating magnetic fields generated by the reader. This allows not only data to be transmitted, but also transponders to be supplied with energy.