An eddy current is a  current set up in a conductor in response to a changing magnetic field. They flow in closed loops in a plane perpendicular to the magnetic field.  By Lenz law, the current swirls in such a way as to create a magnetic field opposing the change; for this to occur in a conductor, electrons swirl in a plane perpendicular to the magnetic field.

According to Faraday is law changing magnetic field produces electric field in a conductor. Electric field in a conductor gives rise to electric current according to ohms law. Or in other words the induced field gives rise to emf which lets current flow in closed loops.  

To minimize the eddy currents,the metal core to be used in an appliance is taken in the form of thin sheets.The planes of these sheets are arranged parallel to the magnetic field so that they cut across the eddy current paths. Large resistance between the thin sheets confines the eddy currents to the individual sheets. Hence the eddy currents are reduced to a large extent.