Sit-ins were a form of nonviolent protest that became an instrumental tactic in the civil rights movement of the 1960s. The sit-in movement began on February 1, 1960, when four African American college students in Greensboro, North Carolina, sat down at a segregated lunch counter at a Woolworth's store and refused to leave. Their peaceful protest sparked a wave of sit-ins across the southern United States, where African Americans and their allies would sit at segregated lunch counters, restaurants, and other public facilities to challenge racial segregation and discrimination.

Sit-ins were a powerful form of direct action, as they disrupted the normal operations of businesses and brought attention to the injustices of segregation. Participants faced verbal and physical abuse, arrest, and violence from segregationists, but their courageous actions brought national attention to the civil rights movement and helped to desegregate public places.

Notable sit-ins include the Nashville sit-ins in 1960, where college students coordinated sit-ins at lunch counters to desegregate downtown businesses, and the Woolworth's lunch counter sit-ins in Jackson, Mississippi, in 1963, where protesters endured violent attacks by white supremacists.

The sit-in movement helped to build momentum for the civil rights movement and paved the way for other forms of nonviolent protest, such as freedom rides and marches. The bravery and determination of those who participated in sit-ins were crucial in challenging segregation and advancing the cause of civil rights in America.