Americans on Monday celebrate Martin Luther King Jr. Day, honoring a man who embodied the U.S. civil rights movement and who understood that the success of the movement depended on its nonviolent principles.

　　Every year on the third Monday in January, Americans honor the slain civil rights leader who in the 1950s and 1960s organized nonviolent protests against Southern segregation, the struggle for black equality and voting rights.

　　Many around the country spend the holiday commemorating King’s tireless work to end racism by participating in community service projects. The U.S. Congress honored that community spirit in 1994 by designating the King holiday as a national day of service.

　　President Donald Trump paid tribute to King during a ceremony in Washington Friday, praising his “peaceful crusade for justice and equality.”