After spilling some liquid on my desk I will remind you the macroscale description of wettability and capillarity followed by experimental examples illustrating that a more appropriate description on smaller is needed scales. Such a description is provided by a mesoscale theory based on wetting potential/disjoining pressure. At this point I switch to pen and pad to discuss some details of the two formulations and their relation. This includes a derivation of the macroscopic Laplace and Young-Dupre laws and of their mesoscale equivalent. These are then used to (i) relate contact angle and wetting potential, (ii) establish consistency relations for the two levels of description, and (iii) discuss the stability of thin films of partially wetting liquids. Finally, it is briefly explained how the mesoscale description feeds into the gradient dynamics approach as explained in detail in the February 2020 SPP Winter School. If time remains, we discuss how wetting potentials can be obtained from microscale models and dwell on an extension of the approach towards complex liquids (surfactant covered films, or films of mixtures).