The name Wayback Machine was chosen as a droll reference to a plot device in an animated cartoon series, The Rocky and Bullwinkle Show. In one of the animated cartoon's component segments, Peabody's Improbable History, lead characters Mr. Peabody and Sherman routinely used a time machine called the "WABAC machine" (pronounced way-back) to witness, participate in, and, more often than not, alter famous events in history.