In Earlier times, Greeks and Etruscans found that a locally found rock, a lodestone, would always point in the same direction.  This is the beginning of the study of magnetism.  Only a few naturally occurring objects exhibit magnetic properties, but electrical currents are also affected by magnetic fields, which makes their study much more important.
    The lodestone, now known as magnetite, is predominantly an iron alloy.  Other elements such as nickel and cobalt can also be magnetized.  Recently, many of the rare earth elements have been made into magnets using a high temperature ceramic process.  The strongest of these are the ones made of neodymium.
    Some magnets are permanent magnets since they do not lose their magnetic ability quickly, but rather stay magnetized for a long time, often for years.  Other magnets are temporary magnets since they lose their magnetic ability very quickly.  A refrigerator magnet would be a permanent, while an electromagnet would be a temporary one.  Materials which are easy to magnetize (such as iron) also lose their ability soon, while those which are hard to magnetize (like nickel and cobalt) tend to hold on to it much longer.