Background: The words autistic and autism from the Greek word autos meaning self were used to refer to individuals who had an extremely narrow range of personal relationships and restricted interactions with their environment: a withdrawal from the fabric of social life into self. Autism spectrum disorders (ASD) involve myriad aberrant perceptual, cognitive, linguistic and social behaviors. Some consistent patterns of behavior accompany autism, but a great deal of variation in symptoms is exhibited by those who are autistic. Not only do the symptoms vary, but severity of the symptoms can be wide ranging. Diagnostic and statistical manual of mental disorders, 5th edition (DSM 5) divides them into two general domains: social communication impairment and repetitive/restricted behaviors. Many children with ASD lack communicative intent and desire to communicate for social purposes. Deficits in social communication are linked to impairment in their joint attention. Some of these children have severe language impairments and some can be mute. They have problems with pragmatics, the social uses of language.

Conclusion: In this article the definition, diagnostic criteria, prevalence, etiology and characteristics of autism spectrum in detail provided