Thermoelectricty is the phenomenon of generation of electric voltages or currents in reponse to temperature gradients. Thermoelectric properties of materials are of interest not just from the point of view of energy generation but also fundamental physics, where they can be studied to shed light on the properties of charged carriers and the role of correlations. In this talk, I will present a review of the thermoelectric properties of text-book metals and semiconductors before moving on to describe the effect that strong correlations have on these systems. I will show that interesting physics such as the violation of the Widemann-Franz law and saturation of thermopower can arise in strongly correlated thermoelectrics using Na_xCoO_2 as an example. Similar physics will also be shown to govern transport through single molecules with strong correlations, giving rise to interesting thermoelectric properties. Finally, I will describe the thermoelectric properties of graphene, especially the role of acoustic phonon scattering and magnetic fields on thermoelectricity.