Investigating the nanomechanical properties of cells, as well as under-standing how cells react to and exert forces within their local environment, has become an extremely important area of research. Atomic force microscopy offers a unique capability to study and ultimately quantify these forces. In this article we describe the various AFM modes and techniques, including PeakForce ONM. Force volume, and force spectroscopy, that are available to researchers and that allow them to measure, map, and apply controlled mechanical stimulations to individual cells. We also present data from a range of research areas in cell biology where these techniques are providing valuable information with regards to the nanomechanical properties of living cells.