Magnets in General
Because of the vast information of magnets, i have chose a few snippets from Wikipedia™. For full information please see http://en.wikipedia.org/wiki/Magnet
Information
A magnet is a material or object that produces a magnetic field. A low-tech means to detect a magnetic field is to scatter iron filings and observe their pattern, as in the accompanying figure. A "hard" or "permanent" magnet is one that stays magnetized, such as a magnet used to hold notes on a refrigerator door. Permanent magnets occur naturally in some rocks, particularly lodestone, but are now more commonly manufactured. A "soft" or "impermanent" magnet is one that loses its memory of previous magnetizations. "Soft" magnetic materials are often used in electromagnets to enhance (often hundreds or thousands of times) the magnetic field of a wire that carries an electric current and is wrapped around the magnet; the field of the "soft" magnet increases with the current.
Magnetic poles
Although for many purposes it is convenient to think of a magnet as having distinct north and south magnetic poles, the concept of poles should not be taken literally: it is merely a way of referring to the two different ends of a magnet. The magnet itself may be homogeneous; there are not distinct "north" or "south" particles on opposing sides, and no Magnetic monopole has yet been observed. If a bar magnet is broken in half, in an attempt to separate the north and south poles, the result will be two bar magnets, each of which has both a north and south pole.
