Low Voltage Wiring
Low voltage wiring is the wiring for audio, video, telephones, alarm systems, HVAC, and generally any wiring for things using less than 24 volts.
Low voltage is often used only with small electrical systems as it is not suitable for large-scale electrical projects. There are very real safety risks associated with low-voltage systems.
Low-voltage can cause unsettling shocks, especially in an unsafe environment, such as ungrounded or standing in a wet area.