Delusions are kind of like hallucinations, except they don’t happen to your senses. Like, you don’t see something that isn’t there, but you will think about things that aren’t real. For instance, a person might think they can talk to ghosts and the ghosts are telling him that the government wants to capture him because of the secret information he knows about aliens! Yes, that’s the kind of thing a person with delusions may think about.
If somebody is paranoid and is having delusions like people don’t like him, then if you say something nice, they may think that you were being sarcastic. You could tell this person that you like his t-shirt, and he may think it’s a joke and that you are making fun of him. That’s how delusions work. They make it so that you don’t understand reality very well and are always twisting it around to fit what your delusions is.
Someone with delusions may do well until they get hit with some kind of stress, like at their job or at home. Then suddenly they start thinking things thataren’t real. They may think everyone is after them, or that they have some amazing plan that is going to make them rich. They can think that there are hidden messages on TV meant just for them and stuff like that. It can get really far out and weird. Delusions don’t sound nearly as fun as hallucinations could be.