Printed electronics is a set of printing methods used to create electrical devices. Paper's rough surface and high water absorption rate has focused attention on materials such as plastic, ceramics and silicon. Printing typically uses common printing equipment, such as screen printing, flexography, gravure, offset lithography and inkjet. Electrically functional electronic or optical inks are deposited on the substrate, creating active or passive devices, such as thin film transistors or resistors. Printed electronics is expected to facilitate widespread, very low-cost, low-performance electronics for applications such as flexible displays, smart labels, decorative and animated posters, and active clothing that do not require high performance.