Magnetism is one of the traditional fields of physics. It is a force of attraction or repulsion that can act over a distance. The name of magnetism comes from a region in Asia Minor known as Magnesia which was a source of lodestone, a naturally occurring magnetic iron ore. Magnets are considered to be dipole which means they come in pairs. A monopole has never been found and when a magnet is broken it immediately forms both poles on both pieces.
Magnetism and Chemical Elements
Almost all elements and compounds have magnetic properties. Diamagnetic materials have a weak repulsion to both poles of a magnet. Paramagnetic materials, become weakly magnetic when near a magnet. Ferromagnetic materials can become permanently magnetized.
Electromagnetism is the study of electromagnetic fields based on the electric charge of particles that make up matter.
Magnetism and Creation
Planetary magnetism is gaining interest regarding support for creation. Geomagnetism and the geomagnetic field decay can be used as evidence of a young Earth. The magnetic fields found on other planets are also signs of a young solar system.
An important aspect of magnetic field lines is that they are like the lines dividing states and countries or perhaps the longitude/latitude lines on an Earth map. Calling them "lines" is useful for reference but as "lines" they are imaginary. This is why discussions of "magnetic disconnection" or "magnetic reconnection" betray a fundamental misunderstanding of magnetism. Imaginary lines cannot connect or disconnect.
Magnetic fields do not exist alone, but require electric current. The common understanding of the "bar magnet" to describe magnetism (see illustration this page) merely depicts the flow of magnetism without describing why this flow occurs. The flow of charged particles through space naturally form a current and thus naturally manufacture a magnetic field. The field is actually the larger expression of the smaller fields around the particles forming the current. Their cumulative effect is a magnetic field circumscribing the motion of the particles, which serves to further confine the particles and thus concentrate the flow of charged particles.