Cognition is sometimes defined as the mental process of knowing, including aspects such as awareness, perception, reasoning, and judgment. In simple terms, cognition means thinking.
Some autistic people have extremely good cognitive skils.
For example, there are numerous autistic people with very successful academic carers, such as Temple Grandin, a professor of animal husbandry at Colorado State University.
However many autistic people struggle with some cognitive tasks and this is not necessarily to do with intelligence.
For example, some academically able autistic people are unable to cross the road by themselves because they are unable to process all of the variables (such as the speed of traffic coming in different directions).