Electronic paper, also called e-paper, is a display technology designed to mimic the appearance of ordinary ink on paper. Electronic paper reflects light like ordinary paper and is capable of holding text and images indefinitely without drawing electricity, while allowing the image to be changed later. Applications of e-paper technology include e-book readers capable of displaying digital versions of books, magazines and newspapers, electronic pricing labels in retail shops, time tables at bus stations, and electronic billboards. Electronic paper was invented in 1973 by Nick Sheridon at Xerox’s Palo Alto Research Center. The first electronic paper, called Gyricon, consisted of polyethylene spheres between 75 and 106 micrometres across.