A device that routes an optical signal from one or more input ports to one or more output ports. It enables signals in optical fibers or integrated optical circuits (IOCs) to be selectively switched from one circuit to another. An optical Switch may operate by (a) mechanical means such as physically shifting an optical Fiber to drive one or more alternative fibers, or (b) electro-optic effects, magneto-optic effects, or other methods. Slow optical switches, such as those using moving fibers, may be used for alternate Routing of an optical Transmission path, i.e routing around a fault. FAST optical switches, such as those using electro-optic or magneto-optic effects, may be used to perform logic operations.