Electric fields are created by the presence of an electrical charge in a conductor. Magnetic fields are created by electrical current - the flow of electrons through a conductor. In simpler terms, electrical fields exist around energized wire, even when an appliance is turned off.
Magnetic fields exist only when the appliance is turned on and the current is flowing.
Either field by itself is harmless. When current flows through a wire both an electrical field and a magnetic field is created - this combination is an electromagnetic field. Since EMFs fall off rapidly in strength with distance from their source, location relative to the source is critical. On a more personal basis, various appliances can emit levels in the hundreds at distances as close as four inches. Although this field potential drops off dramatically at distances of one to three feet from the source, use of certain appliances require close proximity to the user by design.