Alternating Current vs Direct Current: AC vs DC Explained

Direct current (DC) flows in one constant direction, like water through a straight pipe.
Alternating current (AC) switches direction many times per second—60 times per second in the U.S. (60 Hz).
Batteries provide DC, making it ideal for electronics like phones and laptops.
Power plants generate AC because it’s easy to send long distances with little loss.
Transformers can step AC voltage up or down, a trick DC can’t do as easily.
Thomas Edison promoted DC, while Nikola Tesla and George Westinghouse championed AC.
AC won the “War of Currents” for powering cities, but DC has made a comeback.
Modern tech uses both: homes run on AC, but devices convert it to DC inside.
High-voltage DC (HVDC) lines are now used to efficiently connect distant power grids.
From wall plugs to USB cables, AC and DC quietly work together to power our world.