Andrew Jackson was a President of the United States.
During the 1840 election, American Whigs believed the code "OK" was President Jackson's abbreviation for "all correct". It actually the secret name for New York Democrat clubs and stood for "Old Kinderhook", the home of Martin Van Buren. (PROSE: System Shock)
Behind the scenes
Andrew Jackson is referred to as "President Jackson" in System Shock.
He was voiced by Dan Castellaneta in The Simpsons episode, Mobile Homer.