Each year, people across the globe take to the streets to commemorate International Workers' Day, or May Day.
In dozens of countries, May Day is an official holiday, and for labour rights campaigners it is particularly important.
In the United States, it is symbolic of past labour struggles against a host of workers' rights violations, including lengthy work days and weeks, poor conditions and child labour.
Why is International Workers' Day on May 1?
In the late-19th century, socialists, communists and TRADE unionists chose May 1 to become International Workers' Day.
The date was symbolic, commemorating the Haymarket affair, which took place in Chicago, in the US, in 1886.
For years, the working class - often forced to work up to 16 hours a day in unsafe conditions - had been fighting for an eight-hour workday.