It is important to first differentiate molecular motors that operate continuously in a non-equilibrium steady state, which are designated as "information ratchets", from molecular motors ("energy ratchets") and switches operated in a stepwise manner. 10b In the former case, coupling a reaction network associated with molecular motion to a spontaneous chemical process can result in continuous net directional motion provided certain conditions are met. In the latter, external intervention is required to switch the system between different states. Importantly, although at the point of switching (e.g., change of pH, redox potential) the system is not at equilibrium and net flux between species will take place as it relaxes to a new equilibrium position, once equilibrium is reached, the system will remain at an equilibrium steady state until the next stimulus is applied.