Martin Luther King Jr. Day is a federal holiday in the United States of America honoring the birth of Martin Luther King Jr., a prominent civil rights activist. Celebrated on the third Monday in January, the holiday falls close to King's birthday, which is January 15th. This day was established as a holiday in 1986 after a long campaign to recognise King's contributions towards ending racial segregation and discrimination through non-violent means.

The campaign to recognize this day was started by labor unions not long after King's assassination in 1968. However, it wasn't until 1983 that legislation was signed by then President Ronald Reagan making it a national holiday. The holiday, however, was not recognized by all states until 2000. Today, Martin Luther King Jr. Day is observed with various activities across the nation such as parades, community service activities, and school lessons on the Civil Rights Movement.

Martin Luther King Jr. Day is not just a day off from work or school, but it's seen as a day of service to remember his activism. People are encouraged to use this day to contribute to their communities and reflect on the principles of racial equality and nonviolent social changes that King stood for. In this way, Martin Luther King Jr. Day upholds the activist's vision and continues to inspire and educate future generations on the fight for racial equality.