JK flipflop
A JK flipflop is a clocked flipflop whose designation comes from the two information inputs "J" and "K" and is probably due to the developer Jack Kilby. In addition, the JK flip-flop has a clock input (C).
The operation of the JK flip-flop corresponds to that of the RS flip-flop as long as different signals are present at the inputs. If, on the other hand, a "1" is present at each of the inputs "J" and "K", then the JK flip-flop operates like a T flip-flop and is controlled by the clock signal.
The JK flipflop is also called master- slave flipflop because it is composed of two flipflops, a master and a slave, which are controlled by the rising and falling edges of the clock pulse.
JK flipflops are used in shift registers and counters because all flipflops of such a register can be set simultaneously.