Sarcastic Vs Sarcasm

If you complement a pretty, gorgeous girl, and in return she yelled at you and said it is sarcastic, is that true???

Actually, what is sarcasm??? Hmmm..after learned so many things about sarcasm, i think it's kind of insulting people in a soft way. a bit using psychology. After all, whatever i read I need to think first whether it's sarcastic or not. Read between the line.

Sometimes, I'm not sure when I read the article where's the line that said sarcastic. It's a bit tough. Maybe, I'm lack of English words. That's the reason I don't understand so much. Sometimes, when Ms Chan laughed, I didn't understand why she laughed. Maybe I can't get the 'funny' thing.

I should read and understand more about sarcasm because I can see the importance of it in my course. Hope I can laugh in the right place to laugh.