Flip Flops are a great topic, and while they are used for memory it is interesting that flip flop and static memory is no longer used in RAM circuits. While flips flops are randomly accessible in that you can address any memory location in the same amount of time, unlike sequential memory, they are used in high speed cache memory for micros and other high speed digital integrated circuits.

Static memory is not very dense, and a technique known as dynamic memory is more common in RAM chips. Dynamic RAM requires a refresh circuit and use capacitance.

I have a video on static RAM I may post soon, and your article is a great segue for my video. The circuits you mention in the article are very useful.

BTW: You mentioned sequential logic, and I mentioned sequential memory in my comment. Sequential logic as you described means the output depends on the sequence of the inputs, rather than just logic state. Sequential logic is easier to predict as the inputs are clocked and typically edge triggered.

Enjoyed the article! --3D