The Diagnostic and Statistical Manual of Mental Disorders (DSM) defines six subtypes of the disorder characterized as erotomanic (belief that someone is in love with one), grandiose (belief that one is the greatest, strongest, fastest, richest, or most intelligent person ever), jealous (belief that one is being cheated on), persecutory (delusions that the person or someone to whom the person is close is being malevolently treated in some way), somatic (belief that one has a disease or medical condition), and mixed, i.e., having features of more than one subtype.Delusions also occur as symptoms of many other mental disorders, especially the other psychotic disorders. The DSM-IV and psychologists agree that personal beliefs should be evaluated with great respect to cultural and religious differences, since some cultures have widely accepted beliefs that may be considered delusional in other cultures.An earlier, now obsolete, nosological name for delusional disorder was "paranoia". Classification
The International Classification of Diseases classifies delusional disorder as a mental and behavioural disorder. Diagnosis of a specific type of delusional disorder can sometimes be made based on the content of the delusions, to wit,  the Diagnostic and Statistical Manual of Mental Disorders (DSM) enumerates seven types:

Erotomanic type (erotomania): delusion that another person, often a prominent figure, is in love with the individual. The individual may breach the law as they try to obsessively make contact with the desired person. Grandiose type (megalomania): delusion of inflated worth, power, knowledge, identity or believing oneself to be a famous person, claiming the actual person is an impostor or an impersonator.
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