Hyperconjugation
Hyperconjugation is a concept in organic chemistry that explains the stability of molecules by the interaction of a σ-bond with an adjacent empty or partially filled p-orbital or a π-orbital. This phenomenon is based on the delocalization of electrons through overlapping orbitals, which results in stabilization of the molecule.

Brief History
Hyperconjugation was first proposed by Ronald Breslow in 1957 to explain the stability of alkyl cations. He suggested that the interaction between the σ-bond of a C-H bond and the empty p-orbital of a positively charged carbon atom leads to stabilization of the cation. This concept revolutionized the understanding of organic chemistry and provided a new way to explain certain chemical phenomena.

Explanation in Detail
When a σ-bond interacts with an adjacent π-orbital or a vacant p-orbital, it results in the delocalization of electrons, leading to stabilization of the molecule. This interaction helps in distributing the positive charge or electron density over a larger area, reducing the overall energy of the system.
Hyperconjugation plays a crucial role in determining the stability of carbocations, radicals, and double bonds in organic molecules. It also influences the reactivity and selectivity of chemical reactions. Understanding hyperconjugation can help predict the behavior of organic compounds and design new molecules with specific properties.
In conclusion, hyperconjugation is a fundamental concept in organic chemistry that explains the stability of molecules through electron delocalization. It has had a significant impact on the field of chemistry and continues to be a key principle in understanding chemical reactivity.