I read in the "Lessons in Electric Circuit" book, volume 2: "One might wonder why anyone would bother with such a thing as AC. It is true that in some cases AC holds no practical advantage over DC. In applications where electricity is used to dissipate energy in the form of heat, the polarity or direction of current is irrelevant, so long as there is enough voltage and current to the load to produce the desired heat (power dissipation)."
Why is current irrelevant "In applications where electricity is used to dissipate energy in the form of heat"? What's a good example about this?