How can electricity make magnetic fields?

In 1820, Oersted discovered that an electric current can produce a magnetic field. He happened to notice a compass move when he connected a battery to a circuit. Anytime an electric charge moves, it creates an associated magnetic field.

This is when we introduce the "dreaded" right-hand rule. Correctly executing this maneuver will help you determine the direction of a magnetic field associated with an electric current. Please be sure to set your pencil down and make sure you use your right hand, because even if you only mistakenly use your left hand, you will get the wrong direction! If you point the thumb of your right hand in the direction of positive current (which is opposite the direction of the electron current), the fingers of your right hand will naturally wrap in the direction of the magnetic field reaching out in circles perpendicular to the wire.

If we wrap a wire carrying current into a loop, we have the same magnetic field that would appear around an ordinary bar magnet. Another version of the dreaded right hand rule helps us identify the north pole of a solenoid which is just a stack of these loops. If you wrap the fingers of your right hand in the direction of the current in the solenoid, your thumb points in the direction of the north pole of your "electromagnet". If the current is turned off, the magnetic field disappears. If the current is turned on, the magnetic field will appear again.