Abstract: A display system is made up of an array of blocks, each block in turn consisting of rows and columns of individual display units each having a thin, pivotally mounted vane movable by electrostatic forces between an upright (WRITE) position and a horizontal (ERASE) position. A message can be displayed by selection of a pattern of vanes moved from one position to the other. Each vane assembly is symmetrically bistable, being movable in both directions by the same triggering electrodes which are subjected to a short pulse of high D.C. voltage that kicks the vane towards a mid position and subsequently allows it to continue its travel under its own momentum and gravity. Selection of units not to be operated is carried out by means of inhibit electrodes located near the vane in its extreme positions, such electrodes, when energized, preventing movement by the triggering electrodes.