For a lot of people, Labor Day means two things: a day off and the end of summer. But why is it called Labor Day? Labor Day is a day set aside to pay tribute to workmen and women. It has been celebrated as a national holiday in the United States and Canada since 1894.The holiday is more casual that May Day labor celebrations, which tend to be more confrontational celebrations associated with socialism. Get access to all Labor day, International labor day, Labor day images, labor day quotes, happy labor day.