What is organic chemistry definition. Sodium azide is a organic or inorganic compound.?

Can some body tell me what is the exact defination of organic chemistry. I read that compounds with carbon and hydrogen bond or organic. But the oxalic acid is inorganic, sodium carbonate, bicarbonate, carbon graphite etc.. or not organic though they contain carbon. Please some body help me in this regards. Please also let me know how to prove that sodium azide is a organic compound? Please help meee.....