High confinement mode of tokamak plasma without the presence of Edge Localized Modes (ELMs). This mode was discovered on tokamak DIII-D and repeated on other tokamaks. The absence of periodic bursts of energy (so-called ELMs) is positive for the plasma-facing components (wall and divertor), which do not have to endure such a high thermal load and are less at risk of damage, but in turn reduces the transport of impurities outwards from the plasma. Currently, tokamaks are operated in H-mode with ELMs, which are broken down into a larger number of smaller ELMs by various methods.