Almost all of them have European surnames, but only ~20% of them have a European ancestor. If you are white, chances are good one of your ancestors came from France, or used a French surname to fool the authorities.
1 AC, or alternating current means the electrical current is alternating directions in a repetitive pattern.  AC is created by generators in power plants, and other sources. This AC current is delivered to our homes and businesses by the power lines we see everywhere.
There are two main types of current in our world. One is direct current (DC) which is a constant stream of charges in one direction. The other is alternating current (AC) that is a stream of charges that reverses direction. Let's look at DC power which was refined by Thomas Edison in the 1800s. The current in DC circuits is moving in a constant direction.