What was the significance of certain individuals toward the civil rights movement?

Emmett Till, Martin Luther King Jr., and Rosa Parks were some of the most notable individuals who gave rise to the movement. Emmett Till's murder started the civil rights movement after two white men murdered him in 1955. A cashier named Carolyn Bryant alleged that Till sexually harassed her at the store she worked in. Her husband and brother later tracked Till down and shot the boy after torturing him and disfiguring his face. Till's mother insisted on an open casket showing to the public, and the press publicized images of his body. Till's horrid murder shocked the nation and sparked the beginnings of the civil rights movement.
Martin Luther's King Jr.'s espousal of nonviolent protest and peaceful integration brought civil rights to the forefront of national dialogue. King also went on television to spread the message and gave passionate speeches that rallied many to his cause. His presence in the movement played a vital role in the peaceful coexistence of people of different races and changed many hearts and minds in the process.
Rosa Parks fostered the movement when she refused to give up her seat to a white man on a bus in 1955. Her defiance and arrest eventually led to the Montgomery bus boycott. Her involvement also inspired many people to join the cause.
https://www.britannica.com/biography/Emmett-Till

https://www.britannica.com/biography/Martin-Luther-King-Jr

https://www.britannica.com/biography/Rosa-Parks