"The Boy Who Lived" refers to Harry Potter, the main character in the Harry Potter series by J.K. Rowling. He is known for surviving an attack by the dark wizard Lord Voldemort when he was just a baby, which left him with a lightning-shaped scar on his forehead. This event made him famous in the wizarding world, earning him the title of "The Boy Who Lived." As he grows up, Harry discovers his magical heritage and attends Hogwarts School of Witchcraft and Wizardry. Throughout the series, he faces various challenges and battles against Voldemort and his followers, known as Death Eaters, while forming strong friendships with characters like Hermione Granger and Ron Weasley.