Why do people understand nothing about Islam?

Really, I am a Muslim, and it makes me furious to hear about this Quran burning and evil religion crap. So many people think that 1.6 BILLION people are crazy suicide bombers. Just the other day, I went to the store and a guy whispered "suicide bomber". If Islam is made up of all suicide bombers then Germans are all Nazis and the Japanese are all kamikazes. And btw suicide is a sin.