Answer and Explanation:
In J. K. Rowling's "Harry Potter and the Sorcerer's Stone", the main character Harry Potter finds out he is not only a wizard, but supposedly a famous one. When the evil wizard Voldemort tried to kill Harry, he lost his powers and disappeared. However, Harry's parents were killed in the attack, and Harry was left with his uncle and aunt, who are not wizards and who hate magic. Therefore, Harry does not know much about the Wizarding world.
In the train on his way to Hogwarts, the magic school, Harry shares the compartment with Ron, a boy his age who comes from a family of wizards. During their conversation, Harry gets to learn a bit about the Wizarding world:
1. He learns he is not supposed to say Voldemort's name. Wizards normally say You-Know-Who, since they are afraid of the name and of what it represents.
2. People in pictures can move and leave. Unlike pictures in the muggle world (non-wizard world), people in pictures and photos in the Wizarding world can move, talk, and even leave if they want to.
3. There are different Houses in Hogwarts. Each House values a different characteristic in students. Harry becomes hopeful to be selected for the same House as Ron.