Key moment: Black Lives Matter reignited as a cause and rallying cry in 2020 amid mass protests after a police officer murdered George Floyd in Minneapolis.
Historical significance: Three young Black women – Alicia Garza, Patrisse Cullors and Opal Tometi – created the movement with a Twitter hashtag following the 2013 acquittal of the killer of teen Trayvon Martin. The movement gained attention as Black people, including Michael Brown in Ferguson, Missouri, died at the hands of police. The term and the cause became a rallying cry for protests around the globe after Floyd’s death. Research shows teens are more likely to support Black Lives Matter than adults. (Photo by Agustin Paullier/Getty Images)