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Δxmin, Δymin ¼ λ/2n sin α ð Þ λ/2 where λ is the wavelength of the light, n the index of refraction of the microscopy medium and α half the aperture angle of the objective lens.[1] This implies that objects separated by less than 200nm, that is, about half of the wavelength used, cannot be resolved by light microscopy. It was the groundbreaking work of the three Nobel laureates that showed ways to circumvent this limit and transferred optical microscopy into nanoscopy. With super-resolved fluorescence microscopy, scientists are now capable of following the pathway of an individual molecule inside a living cell, observing molecules as they create synapses between nerve cells in the brain, and resolving the aggregation of proteins involved in Parkinson s, Alzheimer s, and Huntington s diseases, to mention only few of the new challenges mastered.[2] How did all this come about? The Nobel laureates developed two different and independent approaches for circumventing the resolution limit and achieving super resolution. One approach uses the detection of single molecules and their precise localization down to few nanometers [3](Moerner 1989) and a strategy [4] to precisely localize many single molecules that define a complex structure (Betzig 1995/2006). The other approach employs patterned illumination to spatially control the emission of excited fluorophores [5](Hell 1994/2000). We first describe the single-molecule-based approach and continue with the patterned illumination technique. In 1952, Erwin Schrçdinger wrote:“[…] we never experiment with just one electron or atom or (small) molecule. In thought-experiments we sometimes …