An ethical hack is when a computer expert is given permission to try to break into a computer system in order to figure out how to protect it better. This is like a game of table tennis, with the computer expert as the player who keeps sending the ball back and the computer system trying to send it back faster and harder each time. The goal is to find the weak points so that they can be fixed. The hacker is like a detective, looking for clues and testing to see what they can do. The end result is a much more secure system.