Benzene has three strongly interacting double bonds
In a benzene molecule every carbon atom is sp2 hybridized with p orbitals that are available to overlap with other atoms.If we have a chain of p orbitals it is because of the alternating sequence of double and single bonds.Conjugation is defined as being a compound that has two double bonds that are separated by just one single bond.In this sort of system the two double bonds are thought of as being conjugated.Double bonds that are involved in conjugated systems have very different properties from those that are isolated.So far we have found that for a compound to be conjugated it must have these two major requirements.
Benzene is a regular heagon because all the bonds are identical.The delocalisation of the electrons means that there aren't alternating double and single bonds.The structure shown above is not how benzene actually is,but it is used for chemical reactions
This is accounted for by the delocalisation of the electrons in the benzene structure.As a general principle the more you can spread around(electrons) the more they are localised,this leads to the molecule being more stable.The extra stability of benzene is ofthen referred to as "delocalisation energy"
If we were to look up the word "conjugated" or " conjugation" in a dictionery we would find that they would be defined as "joined together" and "acting in pairs".This is a fairly accurate way in which to describe the behaviour of the systm.We can summerize the two terms conjugation and delocalisation.we are using conjugation to describe bonds and delocalisation to describe electrons.