Delusions of grandeur is when someone believes that they are very important, special or powerful even though it isn't true. People with this might think that they are a famous person or that they are smarter, more important or better than other people. They might also think that they have special powers like the ability to fly or control the minds of other people. It's important to remember that even though these thoughts might seem true to them, they are not real and it's important to seek help if someone has these ideas.