Flexible PCB(also variously referred to around the globe as flex circuits, flexible printed circuit boards, FPC, flexi-circuits) are members of electronic and interconnection family. They consist of a thin insulating polymer film having conductive circuit patterns affixed thereto and typically supplied with a thin polymer coating to protect the conductor circuits. The technology has been used for interconnecting electronic devices since the 1950s in one form or another. It is now one of the most important interconnection technologies in use for the manufacture of many of today's most advanced electronic products.
In practice there are many different kinds of flexible circuits, including one metal layer, double sided, multilayer and rigid flex circuits.