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An RFID chip (or tag) consists of a tiny chip with wires that serve as an antenna (the x-ray picture below shows the RFID chip in the "Payback" customers card from German retail chain Metro Group). These chips are built into objects, labels oder packaging materials and don't need any batteries of their own. They come alive through radio waves (for the physics freaks: by induction): A reading device, sometimes refered to as "antenna", emits a radio impuls and the spychip returns a number that is stored on it and is unique the world over.

This and more will be explained in detail in our FAQ. Perhaps you would also like to have a look at the position paper that was signed by civil rights campaigners from all over the world.