The Feed-Forward Loop (FFL) is the most common transcription network motif (Milo et al., 2002). In the Coherent type-1 FFL, X activates Y, and both X and Y must be ON to activate Z — creating a sign-sensitive delay: Z responds only after Y accumulates (filters brief pulses), but deactivates immediately when X turns OFF. The Incoherent FFL produces a transient pulse of Z activity. Negative autoregulation speeds response time and reduces noise.