# What is a sp2 and sp3 hybridized bond?

An sp2 hybridization is when an atom (say, carbon in ${C}_{2} {H}_{4}$) has 3 sigma bonds, since pi bonds don't hybridize. Carbon's sigma bonds are the two C-H bonds and the 1 C-C bond in its double bond with carbon.
An sp3 hybridization follows the same concept, except there are four sigma bonds instead of 3, like carbon's hybridization in $C {H}_{4}$.