Computer systems: The d type flip flop
A d-type flip flop is a storage location that can store the value of one bit and flip between the value 0 and 1.
D-type flip flops are combined to create RAM and register memory.
A d-type flip flop has two inputs: A control input (D) & a clock signal.
The D-type flip flop is a positive edge triggered flip flop.
This means the state can only be changed on the uptick of the clock. If you notice the data signal changes from 1 to 0 just after the 6th clock tick but the output does not change until the next uptick.