This lecture by the instructor delves into the fast dynamics of protein machines, focusing on the case of ClpB. It explores the speed limits of conformational changes, the role of free energy barriers, and the mechanisms of substrate translocation. The lecture also covers the interaction of chaperones, the M domain's significance, and the dynamics of pore loops. Through single-molecule FRET studies, the lecture investigates the domain closure in AK, the impact of mutations on protein states, and the regulatory role of the N-terminal domain. Various proposals for the mechanisms of protein machines are discussed, including the power stroke and Brownian ratchet models.