Pervasive developmental disorder, commonly abbreviated as PDD, refers to a group of disorders that affect communication, social interaction, and behavior of an individual. These disorders are diverse and range from autism spectrum disorder to Asperger's syndrome. Although PDD is the commonly used term, some synonyms can be used interchangeably. The synonyms for PDD include autistic spectrum disorder, autism, Asperger's syndrome, atypical autism, childhood disintegrative disorder (CDD), and Rett syndrome. Despite the difference in symptoms and severity among these disorders, they share some common characteristics. These include delays or difficulty in communication, social interaction, and behavior. Proper diagnosis, management, and support can help individuals with PDD improve their quality of life.