Direct Current (DC)

"Direct Current" is produced when Electrons flow constantly in one direction. It is abbreviated as "DC." Since Direct Current flows in one direction only, its electrical pressure or voltage is always oriented in one direction (or "polarity").

Direct Current Flow

Interestingly, the first commercial electrical systems set up by Thomas Edison and others were direct current systems. But, for economic reasons, these were later changed to Alternating Current or "AC" systems, and are described in the Alternating Current Section of this course. Today, Batteries, Solar Panels, Fuel Cells and special "DC" Generators (i.e. Wind Turbines) produce Direct Current.