Atomic force microscopy (AFM) is part of a range of emerging microscopic methods for biologists which offer the magnification range of both the light and electron microscope, but allow imaging under the "natural" conditions usually associated with the light microscope. To biologists, AFM offers the prospect of high resolution images of biological material, images of molecules and their interactions even under physiological conditions, and the study of molecular processes in living systems. This book provides a realistic appreciation of the advantages and limitations of the technique and the present and future potential for improving the understanding of biological systems. The second edition of this bestseller has been updated to describe the latest developments in this exciting field, including a brand new chapter on force spectroscopy. The dramatic developments of AFM over the past ten years from a simple imaging tool to the multi-faceted, nano-manipulating technique that it is today are conveyed in a lively and informative narrative, which provides essential reading for students and experienced researchers alike.