An organic compound is any of a large class of chemical compounds whose molecules contain carbon, with exception of carbides, carbonates and carbon oxides. Organic compounds are studied in organic chemistry; many of them, such as proteins, fats and carbohydrates, are also of prime importance in biochemistry.
The dividing line between organic and inorganic is somewhat controversial
and historically arbitrary, but generally speaking, organic compounds have
carbon-hydrogen bonds, and inorganic compounds do not. Thus carbonic acid is inorganic, whereas formic acid, the first fatty acid, is organic, although it could as well be called "carbonous acid" and its anhydride, carbon monoxide, is inorganic.
The name "organic" is a historical name, dating back to 19th century, when it was believed that o.c.'s can only be synthesised in living organisms through "vis vitalis" - the "force of life".
See list of compounds for a list of all compounds currently in Wikipedia.