Organic compound is a classification for all chemical compounds that contain carbon in them such as isosafrole. As all life that is known is based on organic compounds they remain extremely important. Though some that contain carbon for example carbides, carbonates, cyanides and  oxides of carbon such as CO & CO2 are thought of inorganic.  Petrochemicals in there most basic form are thought of as the building blocks for organic chemistry. Organic chemistry is a science branch that compose a study of all parts of organic compounds. There are multiple ways to classify organic compounds. One such way you can base it of the size of the compound as in small molecules and polymers. Classification can also be divided by the heteroatoms , organometallic compounds which have bonds between between the carbon and metal also organophosphorous compounds which have bonds between carbon and a phosphorous. A major way to classify is by natural and synthetic compounds. Organic compounds examples are lipids which are waxy or fatty type. Proteins which contain nitrogen. It's basically molecules with amino acids that are held together with peptide bonds. Monosaccharides which are simple sugars from a carbohydrates. Polysaccharides are well known they are another group of carbohydrates made up of polymers of simple sugar. Cellulose and glycogen are examples of this. Disaccharides which also are more well known which also carbohydrates consisting of two simple sugars lactose, maltose, sucrose are example of it which you may of heard of. Nucleic Acids are another which is definitely known as all forms of life that we know of need them. They created by a 5-carbon sugar with a phosphate group and nitrogenous base. DNA ( deoxyribonucleic ) and RNA ( ribonucleic acid ) are well known in what makes us life.