Magnets are objects made from materials that are capable of stimulating magnetic reactions. Such reactions are created with the presence of a magnetic field. Examples of these materials are copper, iron, and steel.
The atoms of magnetic materials are arranged in units called domains. A domain is actually a set of numerous atoms that act like a small magnet. If the domains are placed against a strong magnetic field, they are made to move the way the magnetic field does. These domains tend to pull each other together, aligning themselves to become a strong magnet.
The concept of magnetism was first explored by a scientist named William Gilbert. He was the first one to realize that the planet earth is indeed a large magnet. He was also able to discover that magnets can be formed by using twisted iron. After him, a scientist named Hans Christian proved that there is indeed a relationship between electricity and magnetism.
There are basically three types of magnets: temporary magnets, permanent magnets, and electromagnets. Temporary magnets are those materials that elicit magnetic reactions when placed in even weak magnetic fields. However, these materials lose such reactions once the magnetic field is removed. Examples of these materials are Permalloy and soft iron. Permanent magnets, on the other hand, are those that exhibit magnetic properties even without the presence of magnetic fields. Examples are ferrites and alnico.
Meanwhile, electromagnets are built when large magnets are required to perform certain tasks. These magnets are made by placing a metal core inside a coil of wire that carries an electric current.
Today, magnets are used in several kinds of equipment, such as electric motors and generators. Temporary magnets, meanwhile, are used in telephones and televisions. Electromagnets are used in large vehicles like the Maglev train. This type of train operates without wheels. It moves by using a magnetic reaction between the track and the lower portion of the train.