This is the fifth in a series of videos about latches and flip-flops. These bi-stable combinations of logic gates form the basis of computer memory, counters, shift registers, and more. In particular, this video covers the D type flip flop, that is, a master slave configured combination of a gated D latch and a gated SR latch, in which the output of the master is the input of the salve. The video explains the impact of propagation delays in electronic circuits, the importance of selecting an appropriate clock frequency to co-ordinate the operation of logic gates, and the need for bi-stable memory devices that are immune to input fluctuations known as glitches.