Hyperconjugative effect

While a H-C bond is attached to an unsaturated system like double bond or a benzene ring, the sigma (σ) electrons of the H-C bond interact or enter into conjugation along with the unsaturated molecules. The communication among the electrons of  systems (multiple bonds) and the adjacent  bonds (single H-C bonds) of the substituent groups in organic compounds is known as hyperconjugation. The principle of hyperconjugation was organized by Baker and Nathan and is as well termed as Baker and Nathan effect.