Flippity Flop

Computer 'logic" is divided into two categories:  Combinatorial logic is based on
Boolean algebra and does not involve feedback of outputs into inputs,
while sequential logic is based on storage components and feeds outputs
of one operation into a later operation.  The most common storage
component is called a multivibrator or flip-flop, and is built around
two "nor" (or "nand") logic gates that feed back into each other.

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