Electromagnetic propulsion (EMP), is the principle of accelerating an object by the utilization of a flowing electrical current and magnetic fields. The electrical current is used to either create an opposing magnetic field, or to charge a fluid, which can then be repelled. It is well known that when a current flows through a conductor in a magnetic field, an electromagnetic force known as a Lorentz force, pushes the conductor in a direction perpendicular to the conductor and the magnetic field. This repulsing force is what causes propulsion in a system designed to take advantage of the phenomenon. The term electromagnetic propulsion (EMP) can be described by its individual components: electromagnetic- using electricity to create a magnetic field (electromagnetism), and propulsion- the process of propelling something. One key difference between EMP and propulsion achieved by electric motors is that the electrical energy used for EMP is not used to produce rotational energy for motion; though both use magnetic fields and a flowing electrical current.
The science of electromagnetic propulsion does not have origins with any one individual and has applications in many different fields. The thought of using magnets for propulsion continues to this day and has been dreamed of since at least 1897 when John Munro published his fictional story "A Trip to Venus". Current applications can be seen in maglev trains and military railguns. Other applications that remain not widely used or still in development include ion thruster for low orbiting satellites and magnetohydrodynamic drive for ships and submarines.