The chemistry of the element carbon, traditionally excluding the oxides and carbonates. Humans are carbon-based lifeforms, and as such we elevate carbon to a unique place among the elements. Of the six million compounds known, five million are organic.
Carbon is unique for two main reasons.
First, long chains can be built up. Carbon can form two more bonds having made a chain, hence allowing enormous variation in the side chains. Second, carbon is at the top of Group 14 of the periodic table and so is the smallest atom in the group. Carbon atoms can therefore make stronger bonds than silicon atoms can. The higher bond strength means that carbon compounds are much more stable kinetically than the corresponding silicon compounds.