One femtofarad equals 10^-15 farads. Electrical engineers use this tiny unit to measure the parasitic capacitance in integrated circuits and the gate capacitance of individual transistors. As microchips scale down to nanometre dimensions, accounting for single-digit femtofarad values becomes critical to prevent signal delay and cross-talk between tightly packed traces.
Heard on the job
The parasitic routing capacitance on that trace is about 45 femtofarads, which is enough to skew our clock signal.
Insider tip
Engineers often clip this to fF when labeling schematics, usually pronounced as femto-farads rather than spelled out as letters.