Short answers, pulled from the story.
Voltage is defined as work per unit charge in a static electric field. It requires exactly one joule of work to move a single coulomb of charge from point A to point B if the potential difference between them is one volt.
Italian physicist Alessandro Volta lived between 1745 and 1827 before his death. He invented the voltaic pile which stands as possibly the first chemical battery ever created.
Physicists Demetrius T. Paris and F. Kenneth Hurd published Basic Electromagnetic Theory describing how static fields behave differently from dynamic ones in 1969.
Power companies supply consumers with voltages ranging from 110 to 120 volts AC in North America. Most European nations receive power at levels between 220 and 240 volts AC.
C. J. Brockman later analyzed the origin of voltaic electricity in Journal of Chemical Education articles from May 1928. This analysis contributes to understanding the quantity recorded by voltmeters as negative differences of electrochemical potential divided by charge.