In over 80 countries May Day, or International Worker's Day is an official holiday celebrated by millions of people around the world. Organizers in cities across Canada have planned events that we've compiled for our readers below. Click on the links for more info.

But first...here's a brief look back at how it all started:

May Day began in the U.S. as a response to the abuse of state power -- as an international act of solidarity and camaraderie amongst working people everywhere.

Anti-immigrant fervor could be more costly than Arizona lawmakers expected. Thanks to SB 1070, a new law that requires immigrants to carry papers at all times to prove their legal status, the state has become the focal point of the national immigration debate. The bill and the buzz surrounding it illustrates a desperate need for a federal fix to the broken immigration system.

President Barack Obama publicly condemned the measure shortly before Arizona Gov. Jan Brewer signed the bill on April 23, while human rights groups and immigration reform supporters are threatening national boycotts and lawsuits.