Scanning probe microscopy allows a better understanding of phenomena at the nanoscale. The advent of CO-functionalized tips allowed for something extraordinary: atomically resolved images on planar molecules and the elucidation of chemical structures.  
The combination of high-resolution scanning tunneling microscopy and atomic force microscopy has allowed different textbook chemistry concepts (e.g. bond-order, aromaticity and oxidation states) to be probed in unforeseen ways. Moreover, it is possible to characterize batches of synthesized products one-molecule-at-a-time and create a library of observed chemical structures in ways that are prohibitive to standard analytical tools. Here, I will show how high-resolution AFM measurements are performed. Then, we will peruse through different aspects of on-surface reactions and its wonders.