What is the structure of benzene?

Although benzene is often drawn with alternating single and double bonds (Kekule structure), this is not representative of what is actually going on. Refer back to the structure of a C=C double bond, which has two p-orbitals which overap to form a pi orbital. If you were to imagine three double bonds and their p orbitals on the six carbon ring or 'backbone' (comprised of 6 C-C single or sigma bonds) of benzene, you would have six p orbitals, one on each carbon, that all overlap with each other. This is represented as a circle within a hexagon. The electrons are said to be delocalised, meaning they are not confined to individual double bonds, meaning that benzene is planar. In 3D, imagine the planar hexagon with a donut (torus) above and below the plane to represent the six p orbitals overlapping with each other.