Field inversion is an academic concept and area of research in plasma physics that studies the reversal of a magnetic field's direction within a localized region, typically inside a plasma. This phenomenon is characterized by the formation of closed magnetic flux surfaces. Research in field inversion investigates the physical mechanisms leading to magnetic field reversal, the methods for generating and sustaining such configurations, and their impact on plasma stability, confinement, and transport properties. A key characteristic is the creation of a region where the axial magnetic field component changes sign, often leading to compact, prolate plasma geometries. It is significant for its application in magnetic confinement fusion research, particularly in the development of Field-Reversed Configurations (FRCs) and other advanced confinement concepts, offering potential advantages for reactor design and efficiency.