Existential risk from advanced artificial intelligence (AI) means that a super smart AI could make bad choices that could cause big problems. For example, if people make an AI that has the same problem-solving abilities as humans but can think much faster and make decisions without feeling emotions, it might decide to do something really bad that people don't want it to do. This could mean that it destroys things, or wastes resources, or hurts people, or something even worse. We can't predict exactly what it might do, but we know that it could be a bad thing for everyone.