The Charlie Card is what is used for fares on the MBTA, the Boston transit system. This was created several years ago and the theme was based on a song
that was made popular by the Kingston Trio in 1959.
The well-known folk song about Charlie on the M.T.A. is actually entitled "M.T.A.," which stands for Metropolitan Transit Authority, the predecessor of today's MBTA (Massachusetts Bay Transportation
Authority). The song was written as a campaign song for the 1949 Boston mayoral race of Walter A. O'Brien, Jr. (changed by the Kingston Trio to "George
O'Brien"), who was the candidate of the Progressive Party. The song was meant to call attention to O'Brien's opposition to the recent fare increase,
which saw subway riders charged an extra nickel to exit trains at stops above ground.