DC characteristic #4: Quiescent supply current (ICC)
CMOS devices consume much lower current than other types of device when they are inactive.
DC characteristics of the 74VHC04
Example: Quiescent supply current (ICC) vs supply voltage (VCC) curve of the 74VHC04
The quiescent supply current (ICC) of the CMOS device is leakage only and as low as several nanoamperes (nA).