Atomic force microscopy (AFM) was invented in 1986 by Binnig, Quate, and Gerber as “a new type of microscope capable of investigating surfaces of insulators on an atomic scale.” Stemming from developments in scanning tunneling microscopy (STM), it became possible to image insulators, organic and biological molecules, salts, glasses, and metal oxides — some under a variety of conditions, e.g., ambient pressure, in aqueous or cryogenic liquids, etc. In 1987, Mate and co-workers introduced a new application for AFM where atomic-scale frictional forces could be measured. Likewise, in 1989, Burnham and Colton used the AFM to measure the surface forces and nano-mechanical properties of materials. Today, there are many examples of using AFM as a high-resolution profilometer, surface force probe, and nanoindentor. Several new imaging techniques have been introduced; each depending on the type of force measured, e.g., magnetic, electrostatic, and capacitative. Because of the diverse nature of the field and instrumentation, the names “scanned probe microscopy” and “XFM” (where X stands for the force being measured, e.g., MFM is magnetic force microscopy) have been adopted.