Not a long time ago, the resolution of light microscopes was limited by the wavelength of the light. The highest achievable resolution was limited by principles connected to the laws of diffraction. This means that details finer than 200 nanometers (millionths of millimeters) could not be observed. There were however other microscopy techniques available which could provide higher resolution information on a sample’s surface or volume but in a non-optical manner. Among these, we mention electron microscopy or scanning probe microscopy, which were facing however other limitations related to sample preparation, sample roughness, in vivo experiments, and others. Recently, new light microscopy techniques have been developed which surpass the limitations mentioned above. These new techniques have not yet fulfilled complete maturity, but have proven to be solid solutions for imaging optical details in nano resolution in many experiments.