Displacement current is a concept in electromagnetism that describes the flow of electric charge that occurs due to a changing electric field in a region of space.

It was first introduced by James Clerk Maxwell as part of his famous set of equations, known as Maxwell’s equations, which describe the behavior of electric and magnetic fields.

Displacement current is not an actual current of charged particles like the current flowing through a wire. Rather, it is a mathematical construct that describes the flow of electric charge due to changes in the electric field.

The magnitude of the displacement current is proportional to the rate of change of the electric field and is given by the equation I_d = ε_0 (dE/dt), where I_d is the displacement current, ε_0 is the permittivity of free space, and dE/dt is the rate of change of the electric field.