Proton radius puzzle: The present status

I will speak about the so-called proton radius puzzle, which is from a formal point of view the biggest discrepancy within the Standard Model (of about 7-8 sigmas). The proton radius can be determined by three completely different methods and they lead to controversial results. While the results from the phenomenological evaluation of the elastic electron-proton scattering data and from spectroscopy of ordinary hydrogen are in perfect agreement one to the other, they strongly disagree with a much more accurate result from the Lamb shift in muonic hydrogen. The discrepancy between the combined scattering-hydrogen value and the muonic one is from 7 to 8 sigmas. Since the results from ordinary and muonic hydrogen deeply involve QED, the discrepancy is often considered not as a discrepancy between the data, but as a discrepancy between theory and experiment. I will consider the present situation in detail and will discuss all three methods.