To oversimply things, you can imagine current as the electrons passing through a certain point, example the wire or motor. However, the electrons won't move unless a force is applied on them to make them move. Voltage is this force, which is why it's also called electromotive force or e.m.f. Voltage, and more specifically voltage difference provides the force that pushes the electron, or current, through the circuit.
Hope I answered your question.
