Delusions are false beliefs that are strongly held despite evidence to the contrary. They can occur in various mental health conditions, such as schizophrenia, bipolar disorder, and delusional disorder. People experiencing delusions may believe they are being persecuted, have special powers, or are under constant surveillance. These beliefs can significantly impact a person's behavior and daily life. For example, someone with a delusion of grandeur might act as if they are famous or have extraordinary abilities. Treatment often involves therapy and medication to help manage symptoms and improve overall functioning.