An electric current flows when electrons move through a conductor. These electrons are free or loosely bound electrons in the atoms of the conductive material. When a voltage or potential difference is applied across the conductor, it creates an electric field that exerts a force on these free electrons, causing them to move in a coordinated fashion through the conductor. This uniform motion of electrons is what constitutes the electric current. The movement requires a complete path or circuit, so electrons have a place to come from and a place to go. The flow of electrons is continuous only when there is an unbroken conductive path. Electrons flow from the negative terminal to the positive terminal in a typical circuit, driven by the electric field created by the applied voltage. In summary: Electric current flows when free electrons move through a conductor under the influence of an electric field created by an applied voltage, and there is a continuous path for their movement.