They often suffer discrimination, intolerance and isolation, resulting in many feeling excluded from everyday society.
In an attempt to understand the reasons behind this, The National Autistic Society (NAS) commissioned research into levels of awareness and understanding of autism among the public. It published a report on its findings in June 2007.
Overall, the research shows that awareness of autism is high, but that there's a lack of understanding about what it really means to live with the condition. This has a negative effect on people with autism and their families.
The research also shows that people think more positively once they know a person has autism. However, there's a significant gap between those good intentions and the reality experienced by people living with the condition.
The main findings of the research are summarised below.
Awareness of autism is high, but awareness that Asperger syndrome is a form of autism is low.
Of those surveyed, 92% had heard of autism, but far fewer had heard of Asperger syndrome (just 48%). Asperger syndrome is mostly a hidden disability, meaning it is difficult to tell whether someone has the condition from their outward appearance.
While there are similarities with autism, people with Asperger syndrome have fewer problems with speaking and are often of average or above-average intelligence. They do not usually have the accompanying learning disabilities associated with autism, but may have specific learning difficulties. These can include dyslexia, dyspraxia, attention deficit hyperactivity disorder (ADHD) or epilepsy.
Autism is much more common than people realise.
Respondents were asked how many people they think are affected by autism. The majority (90%) didn't know how common it is.
There are more than half a million people with autism in the UK - the equivalent of 1 in every 100 people.
There's a lack of awareness and understanding about some of the key characteristics of autism.
Many people correctly identified some of the key characteristics of autism, including difficulty communicating, difficulty making friends, a love of routine and obsessive behaviour.
However, some other common characteristics, such as the need for clear and unambiguous instructions, being disturbed by noise and touch, and having difficulty sleeping, were less well known. 10% of people thought autism was not a disability.
There's a misconception that people with autism have special abilities.
More than a third of respondents (39%) thought most people with autism have special abilities, such as in maths or art. In fact, it's estimated that just 1 in 200 people with autism has special abilities.
People wrongly believe autism mostly affects children.
More than a quarter (27%) of those who had heard of the condition mistakenly thought it mostly affects children. A child with autism grows up to be an adult with autism.
People don't realise that there's no cure for autism.
There was considerable confusion about whether autism can be cured. Much less than half (just 39%) were aware that there is no cure. Despite this, access to the right help and support can greatly enhance the lives of people with the condition.
A representative sample of more than 2,000 adults aged 16 and over was surveyed across 175 sites in England, Wales, Scotland and Northern Ireland. The report, called "Think differently about autism", can be viewed here.
Article provided by NHS Choices