Organic Chemistry is the chemistry of the millions of carbon compounds that are used in living creatures. Inorganic Chemistry is the chemistry of all compounds except those involving carbon. There are a very few carbon compounds not used in in living tissues such as diamond or graphite. Long bonded chains of one element are rare. Carbon also has 4 valence electrons that are available for bonding.
Most elements have only one or two or three.
The active nonmetals hold electrons so strongly that they usually don't form covalent bonds with other elements. Organic compounds tend to be nonpolar and tend to react slowly unless heated. When organic compounds are heated, they tend to become unstable and increase their reachion rates with oxygen in the air to produce burning. Hydrocarbons are a group of organic compounds containing only carbon and hydrogen. These are primary constitutients of oil and natural gas.