It is a current which produces in the region in which the electric field and hence the electric flux changes with time.
Displacement current, ID = εo . dφE / dt
where, φE is the electric flux.
where, μo = Permeability
= 4π * 10-7 V / Am
This equation is Gauss’s law in electrostatics.
This equation is Gauss's law in magnetostatics.
This equation is Faraday’s law of electromagnetic induction.
This equation is Ampere-Maxwell law.