Complex sentence: Plasma electrolytic oxidation, or microarc oxidation, is an electrochemical process based on the anodising of certain metals, but it employs higher potentials, so that discharges occur.
Split into simpler sentences: Plasma electrolytic oxidation, or microarc oxidation, is an electrochemical surface treatment process for metals. It is similar to anodising, but it employs higher potentials, so that discharges occur.