Today is May Day, which to many may bring visions of maypoles, baskets of flowers and dancers. But in everywhere else except the United States, May Day is Labor Day, alternatively known as International Worker’s Day, or the Day of the Martyrs of the Revolution. Ironically, since the holiday is not officially celebrated here, International Worker’s Day commemorates an event in the United States, the shooting of four protesters in Chicago’s Haymarket Square in 1886. Here to tell us more about the history and tradition of May Day are labor historian Jerry Chernow and former union steward Marty Kehrein. Both are members of the International Workers of the World.