Many autistic people are reported to have behaviours of concern, also known as challenging or disruptive or distressed behaviours. But these are such vague terms that it is important to understand what they mean.
For some people, the term is wide-ranging and refers to anything an individual may do which is inappropriate. So it can include problems as diverse as refusing food, staying awake all night, wetting the bed, removing clothes in public or flicking fingers. Of course, what seems inappropriate to one person may seem perfectly reasonable to someone else.
For some people, the term refers only to those behaviours which are likely to cause significant harm to the individual or to his or her carers. So it is restricted to problems such as aggression, self injury, throwing tantrums or wandering off unsupervised. Again, what seems to be challenging or harmful to one person may seem perfectly reasonable to someone else.
Some autistic people claim that they don't have behaviours of concern, they just behave differently to everybody else. In their view, 'neuro-typical' people are just as likely to behave strangely, for example by using idioms that people with autism can't understand.