How to explain emoticons to an autistic person? I am currently chatting in an IRC and there is one girl (i think she's about 18 years old) and she has Asperger syndrome and therefore is unable to understand countenance and feelings. She told me that she only knows of happiness, sadness and rage but doesn't really understand what each means.

Furthermore the other people use emoticons like :), :(, &gt;:[, ^^, ... and she really has problems to follow the discussion because she is really confused about all of this and when I tell her what each emoticon means five minutes later she will not be able to distinguish between these.

Do you have any suggestions on what to do to reassure her and maybe help her a bit so that she could enjoy the chat like everyone else, more or less? (Although I know she won't understand everything...)
First question, how deep is your knowledge about autism and Asperger Syndrome? Do you understand how autistic people think? Do you understand, what this girl have meant, when she have written, she doesn't really understand what each means?

For neurotypical person, a typical use-case for I understand you phrase is I know what you feel. But autistic people by understand mean in the first line to know the cause-and-effect. So your friend saying she don't understand what really each emotion means, could as good mean: I don't know how particular emotions are affecting the meaning of words the given person use. 

If you want to explain emoticons to her, you should IMHO in first line explain, how particular emoticon in modifying the meaning of the sentence. So, think of emiticons not as the way to communicate emotions (which is of low importance to autistic people) but as the modifiers that change the meaning of the sentence or of the particular words.