Definition: Alternating Current (AC) is a type of electrical current, in which the direction of the flow of electrons switches back and forth at regular intervals or cycles.
Direct current (DC) is electrical current which flows consistently in one direction.
DC is more efficient than AC power and has lower line losses than AC lines. With AC, the current travels on the skin of the conductor while with DC, the current flows throughout the entire conductor and not just the conductor skin.
AC current flows through outer surface due to 'Skin Effect'. Whereas DC current flows throughout the whole cross section diameter of conductor. So DC cable needs Single Strand but AC cable needs Multistranded Copper or Aluminium Conductor bunch for their efficient flow of current.
Direct current or DC electricity is the continuous movement of electrons from negative to positive through a conducting material such as a metal wire. ... In a circuit, the direction of the current is opposite the flow of electrons. DC electricity in a circuit consists of voltage, current and resistance.