May 1st, International Workers' Day, celebrates the historic struggle of working people throughout the world and social and economic achievements of the international labour movement.
International Worker’s Day commemorates the Haymarket Massacre in Chicago in 1886 when police opened fire on workers who were striking for the eight hour day. Three years later, at the first congress of the Second International call for demonstrations on May 1 next year were announced and on the next congress in 1891 was established as the International Worker’s Day. Since then May Day was celebrated by workers, trade unions, various communist and socialist parties and anarchist. After the October revolution it became a national holiday in USSR and later in countries of the Eastern Bloc, China and Cuba.

The UN itself backed workers rights by incorporating several into two articles of the United Nations Declaration of Human Rights.
Article 23

1. Everyone has the right to work, to free choice of employment, to just and favorable conditions of work and to protection against unemployment.
2. Everyone, without any discrimination, has the right to equal pay for equal work.
3. Everyone who works has the right to just and favorable remuneration ensuring for himself and his family an existence worthy of human dignity, and supplemented, if necessary, by other means of social protection.
4. Everyone has the right to form and to join trade unions for the protection of his interests.

Article 24

1. Everyone has the right to rest and leisure, including reasonable limitation of working hours and periodic holidays with pay.

Many of the rights won by the international labor movement have been challenged and restricted in recent time as the very fundamental rights as the right to work or the right to unionize. It is necessary to protect these rights in order to build more just societies and eradicate poverty.