A circuit element that has two stable states, and which the transient application of one or other signals can be made to change state A bistable often has two outputs - the complement (opposite) of one another, Reset (set to 0) and Preset (set to 1) signals, and means of changing state - typically a JK type where the state of two inputs determines what happens during a clock cycle, and Edge triggered where the state of one input becomes the new output state at the rising or falling edge of the clock signal See also Metastable and Monostable