Pi electrons are a type of electron found in certain chemical bonds, specifically in double bonds and triple bonds. They are part of the pi bonds that form when two atomic orbitals overlap sideways. This overlap allows the electrons to be shared between the atoms, contributing to the stability of the molecule. In organic chemistry, pi electrons play a crucial role in the reactivity of compounds. They are often involved in aromatic compounds, where they can delocalize over multiple atoms, creating a stable structure. This delocalization is key to many chemical reactions and properties of these molecules.