A developmental disorder that affects communication and behavior, and includes symptoms that impair the individual's ability to function properly in school, work and other areas of life. Although autism can be diagnosed at any age, it is said to be a "developmental disorder" because symptoms generally appear in the first two years of life. Autism is also known as a "spectrum" disorder because there is wide variation in the type and severity of symptoms people experience. People with ASD have difficulty with social communication and interaction (e.g. lack of eye contact, voice tones that sound sing-song or robotic, facial expressions or gestures that don't match what is being said), restricted interests (e.g., intense interest in numbers, details, facts), restrictive/repetitive behavior (e.g., repeating words or phrases, getting upset at changes in routine or sensory input such as light or noise). People with ASD may also experience sleep problems or irritability, but also have many strengths including the ability to learn things in detail and remember information for long periods of time; being strong visual and auditory learners; and excelling in math, science, music or art. But although ASD can be a lifelong disorder and while children who have ASD have difficulty in talking, playing with other children, and relating to others, including their own family, treatment and services can improve their symptoms and ability to function.