Organic compounds are chemical compounds primarily composed of carbon and hydrogen atoms, often with other elements such as oxygen, nitrogen, sulfur, phosphorus, and halogens present. These compounds form the foundation of organic chemistry, a branch of chemistry that focuses on the study of carbon-containing molecules and their properties, structures, reactions, and synthesis.

Key characteristics of organic compounds include:

1.  Carbon Backbone: Organic compounds are characterized by the presence of carbon atoms forming the backbone or skeleton of the molecule. Carbon has a unique ability to form stable covalent bonds with itself and with other elements, resulting in a wide variety of molecular structures.
2. Functional Groups : Organic molecules often contain specific arrangements of atoms or bonds known as functional groups. These groups impart distinct chemical properties and reactivity to the molecule. Common functional groups include hydroxyl (-OH), carbonyl (C=O), amino (-NH2), and carboxyl (-COOH), among others.
3. Hydrocarbons: Many organic compounds consist solely of carbon and hydrogen atoms and are classified as hydrocarbons. Examples include alkanes, alkenes, alkynes, and aromatic hydrocarbons.
4. Diverse Properties: Organic compounds exhibit a wide range of physical and chemical properties, including solubility, boiling and melting points, acidity or basicity, and reactivity. These properties vary depending on factors such as molecular structure, functional groups, and intermolecular forces.
5. Biological Importance: Organic compounds are essential components of living organisms and play critical roles in biological processes such as metabolism, growth, and reproduction. Biomolecules such as proteins, carbohydrates, lipids, and nucleic acids are examples of organic compounds found in living systems.
6. Synthetic Applications: Organic chemistry is instrumental in the synthesis of a vast array of compounds with diverse applications, including pharmaceuticals, agrochemicals, polymers, dyes, flavors, fragrances, and materials science.

Overall, organic compounds are incredibly diverse and ubiquitous in both natural and synthetic environments, making them central to many aspects of chemistry and everyday life.