There is a lot of useful information out on the net, such as this site:
http://www.udel.edu/bkirby/asperger/

but I suppose a brief summary might be that AS is the higher functioning end of the autistic spectrum, but the Triad of Impairment that would lead to an autistic diagnosis is present i.e. lack of social interaction ( seen as difficulties with relationships),social communication ( referring to verbal and non-verbal use and understanding of language and imagination ( difficulties in
developement of imagination).For any other "symptom", that can be as varied as individuals inevitably are.

There is some link between AS and schizophrenia, but I don't believe it has been established as yet, whether it is causal, mis-diagnosis or some other possibility.Sorry, it really isn't possible to be pithy with such a complex condition although there have been lots of interesting discussions on here about AS.